After discussing with Nerda some of the gear issues he had when it came for gearing up for Kara, I found this post on the blizz forums. Hopefully it will be of some use...
This is a collection of what I consider to be the best pre-raid mage gear (that is, before walking in the door of Karazhan. Kitted out in the best of these, the first few bosses of Karazhan should not be a significant challenge gearwise). Each section is listed by first source (I.e. Crafted/Heroic/else), and, within each category, by my opinion of their usefulness, the best at the top. Generally speaking Craftables > Heroic loot > normal/quest. This is not always the case. Since I cannot make tables easily, you will simply have to compare them yourselves, I'm afraid.
If you think I have missed something else, misplaced something, or generally made an error, please point it out! If it's not too outrageous, I'll change it.
A few general trends: this is aimed towards raiding. Hence, spell hit is given some considerable weighting in the way I have ordered this. It is not intended to gear you up for high end PvP.
Of the Dungeon sets, Oblivion (the Warlock set) features fairly prominently. Incanters not at all, as I consider it a poor set (you may disagree). Mana-etched (the "generic" cloth set) features to some extent, although, generally, it is inferior to other, non set items, unless you get enough for the set bonuses.
Head Crafted Spellstrike Hood; Tailor Made;
http://www.thottbot.com/i24266 Destruction Holo-gogs; Engineering made, BoP;
http://www.thottbot.com/i32494 Heroic Mana-binder's Cowl; 50 badges;
http://www.thotbott.com/i32089 Demonfang Ritual Helm; Underbog: The Black Stalker;
http://thottbot.com/i27781 Normal/Quest Mag'hari Ritualist's Horns; Mag'har Questchain: Horde Only;
http://thottbot.com/i28169 Mana-etchd Crown; Black Morass, Aeonus;
http://www.thottbot.com/i28193 Incanters Cowl; Mechanar, Pathaleon;
http://www.thotbott.com/i28278 Evoker's Helm of Second Sight; Teron Gorefiend questchain;
http://thottbot.com/i31104 Enchant: Glyph of Power; Sha'tar Revered
Shoulder Crafted Frozen Shadoweave Shoulders; Tailoring BoP. Frost only;
http://www.thottbot.com/i21869 Heroic Mana-Etched Spaulders; Slave pens, Quagmirran;
http://thottbot.com/i27796 Normal/Quest
Mantle of Three terrors; Black Morass, Temporus
Spaulders of the Torn heart; Cypher of Damnation Questline;
http://www.thottbot.com/i30925 Spaulders of Oblivion; Shadow labyrinth, Murmur;
http://thottbot.com/i27778 Incanter's Pauldrons; Steamvaults, kalithresh;
http://www.thotbott.com/i27738 Enchant: Aldor/Scryer Inscription
Cape Crafted Cloak of the Black Void; recipie BoE world drop recipie, tailor;
http://thottbot.com/i24252 Heroic Shawl of Shifting Probabilities; 25 badges;
http://www.thottbot.com/i29369 Normal/Quest Sethekk Oracle Cloak; Talon King Ikiss, Sethekk Halls;
http://thottbot.com/i27981 Baba's Cloak of Arcanistry; Mechanar, pathaleon the Calculator;
http://thottbot.com/i28269 Sargeants Heavy Cape; PvP;
http://www.thottbot.com/i28378 Terokk's Wisdom; Terokk, Skettis; BoE epic;
http://thottbot.com/i32541 Cloak of Woven Energy; Hitting the Motherlode, Netherstorm;
http://thottbot.com/i29813 Enchant: Spell Penetration (+20 Spell Penetration)
Or Subtlety (-2% threat). This only worth it on a cloak you will have for a long time, and if Threat is your limiting factor.
Chest Crafted Spellfire Robe; Tailor made, BoP, Fire/Arcane;
http://www.thottbot.com/i21848 Frozen Shadoweave Robes; Tailor made BoP, Frost;
http://www.thottbot.com/i21871 Heroic Mana-etched Vestments; Old Hillsbrad, Epoch Hunter;
http://thottbot.com/i28191 Normal/Quest Robes of the Crimson Order; BoE world drop;
http://www.thottbot.com/i31297 Vermillion Robes of the Dominant; Steamvaults, Kalithresh;
http://thottbot.com/i27799 Bloodfyre Robes of Annihilation; Mechanar, Cahce of the Legion;
http://thottbot.com/i28252 Will of Edward the odd; BoE world epic drop;
http://thottbot.com/i31340 Robes of Oblivion; Shadow labyrinth, Murmur;
http://thottbot.com/i28232 Warp Infused Drape; Botanica, Warp Splinter;
http://thottbot.com/i28342 Incanter's Robe; Botanica,Warp Splinter;
http://thottbot.com/i28229 Enchant: Exceptional Stats (+6 all)
Restore Mana Prime (+6mp5)
Exceptional Spirit (+15)
Bracers Crafted Bracers of Havok; recipie BoE world drop, Tailor;
http://thottbot.com/i24250 Heroic Crimson Bracers of Gloom; Ramparts, Omorr;
http://www.thottbot.com/i27462 Bands of Rarefied magic; Shattered Halls, Kargath Bladefist;
http://thottbot.com/i29255 Normal/Quest Crystalweave Bracers; Created from a 'Depelted' item from Ogri'la. BoE;
http://thottbot.com/i32655 Veteran's Silk Cuffs; PvP;
http://www.thottbot.com/i32820 Shattrath Wraps; The Soul Devices (SL);
http://www.thottbot.com/i28174 Enchant: Spell Power (+15 spell damage)
Gloves Crafted Spellfire Gloves; Tailor made, BoP, Fire/Arcane;
http://www.thottbot.com/i21847 Heroic Mana-etched Handwraps; Ramparts, Omorr;
http://thottbot.com/i27465 Normal/Quest Gloves of Oblivion; Shattered Halls, Kargath Bladefist;
http://www.thottbot.com/i27537 Incanter's Gloves; Steamvaults, Thespia;
http://www.thotbott.com/i27508 Energis Armwraps; Botanica, High Botanist Freywinn;
http://thottbot.com/i28317 Tempest's Touch; Old Hillsbrad Quest;
http://thottbot.com/i29317 Enchant: Spell Strike (+15 Spell hit)
Or Spell Power (+20 Spell damage)
Belt Crafted Belt of Blasting; Note: BoE, but requires Nether Vortex. Will be -very- expensive to buy, if available at all;
http://www.thottbot.com/i30038 Spellfire Belt; Tailor made, BoP, Fire/Arcane;
http://www.thottbot.com/i21846 Girdle of Ruination; Tailor made;
http://www.thottbot.com/i24256 Heroic Belt of Depravity; Arcatraz, Harbringer Skyriss;
http://www.thottbot.com/i29241 Oracle Belt of Timeless Mystery; Underbog, Quagmirran;
http://thottbot.com/i27768 Normal/Quest Sash of Serpentra; Steamvaults, Warlord Kalithresh;
http://www.thottbot.com/i27795 General's Silk Belt; PvP;
http://thottbot.com/i28409 A'dal's Gift; Arcatraz Key quest;
http://www.thottbot.com/i31461 Enchant: None exist
Leggings Crafted Spellstrike Pants; Tailor made;
http://www.thottbot.com/i24262 Heroic Breeches of the Occultist; Black Morass, Aeonus;
http://thottbot.com/i30531 Kirin Tor Master's trousers; Shadow Labyrinth, Murmur;
http://www.thottbot.com/i30532 Mana-etched Pantaloon; Underbog, the Black Stalker;
http://www.thotbott.com/i27907 Normal/Quest Devil Stitched Leggings; Laj, Botanica;
http://www.thottbot.com/i28338 Trousers of Oblivion; Talon King Ikiss, Sethekk Halls;
http://www.thottbot.com/i27948 Incanter's Trousers; Talon King Ikiss,Sethekk Halls;
http://www.thotbott.com/i27838 Khagar's Kilt of Abjuration; Black Morass, Temporus;
http://thottbot.com/i28185 Enchant:
Mystic Spellthread (+25 damage, +15 stamina)
Or Runic Spellthread (+35 damage, +20 stamina)
Boots Crafted Frozen Shadoweave Boots; Tailor made, BoP, Frost;
http://www.thottbot.com/i21870 Boots of blasting; Tailor made, BoP. Recipie a non-binding trash drop in SSC/The Eye. -May- be able to find it on the AH;
http://www.thottbot.com/i30037 Heroic Boots of Etheral Manipulation; Warp Splinter, Botanica heroic;
http://www.thottbot.com/i29258 Boots of Blasphemy; Quagmirran, Slave Pens heroic;
http://www.thottbot.com/i29242 Extravagant Boots of malice; Tavarok, Mana Tombs heroic;
http://www.thottbot.com/i27821 Normal/Quest Sigil-Laced Boots; Arcatraz, Harbringer Skyriss;
http://thottbot.com/i28406 Silent Slippers of meditation; Shadow labyrinth, Murmur;
http://thottbot.com/i27902 Shattrath jumpers; Quest in Shadow Labyrinth;
http://www.thottbot.com/i28179 Enchant: Fortitude (+12 stamina)
Vitality (+4 H/Mp5)
Weapon Crafted One-handed Eternium Runed Blade; Blacksmith made;
Held in Offhand Staves Heroic One-handed Held in Offhand Khadgar's Knapsack; 25 badges;
http://www.thottbot.com/i29273 School-specific offhand; 25 badges
Staves Terokk's Shadowstaff; Sethekk Halls, Talon King ikiss;
http://thottbot.com/i29355 Grand Scepter of the Nexus-Kings; Mana Tombs, Nexus prince Shaffar;
http://www.thottbot.com/i27842 Normal/Quest One-handed Blade of Wizardry; BoE World drop;
http://www.thottbot.com/i31336 Stormcaller / Blade of the Archmage; Thrallmar/Honour Hold exalted;
http://www.thottbot.com/i29155 /
http://www.thottbot.com/i29153 Greatsword of Horrid Dreams; Murmur, Shadow labyrinth;
http://www.thottbot.com/i27905 Continuum Blade; Keepers of Time revered;
http://thottbot.com/i29185 Held in Offhand Crystal Orb of Enlightenment; Ogri'la Exalted;
http://www.thottbot.com/i32651 Lamp of Peaceful Radiance; Harbringer Skyriss, Arcatraz;
http://www.thottbot.com/i28412 Star-heart Lamp; Temporus, Black Morass;
http://www.thottbot.com/i28187 Staves Bringer of Death; BoE world drop;
http://www.thottbot.com/i31308 Aucheni Staff; Aldor Rvered;
http://thottbot.com/i29130 Enchant: Major Spell Power (+40 spell damage)
Wand Crafted None exist
Heroic The Black Stalk; The Black Stalker, Underbog Heroic;
http://www.thottbot.com/i29350 Normal/Quest Nether Core's Control Rod; Dalliah, Arcatraz;
http://www.thottbot.com/i28386 Nexus Torch; Shattered Halls, Kargath Bladefist;
http://www.thottbot.com/i27540 Wand of the Netherwing; Blackheart the Inciter;
http://www.thottbot.com/i27890 Illidari Rod of Discipline; Only a green, but the socket allows considerable upgrade over blue, even epic wands;
http://thottbot.com/i32872 Enchant: None exist
Neck Crafted None to speak of
Heroic Manasurge Pendant; 25 Heroic Badges;
http://www.thottbot.com/i29368 Hydra-fang Necklace; The Underbog, Ghaz'an;
http://thottbot.com/i27758 Normal/Quest Brooch of Heightened Potential; Shadow labyrinth: Blackheart the Inciter;
http://thottbot.com/i28134 Charlotte's Ivy; BoE World Drop. Part of a set with Lola's Eve (ring). ;
http://thottbot.com/i31338 Warp Engineer's Prismatic Chain; Mechanar, Mechano Lord Capacitus;
http://thottbot.com/i28254 Enchant: None exist
Rings Crafted The Black Pearl; Jewelcrafter. Trainer recipie;
http://thottbot.com/i32774 Heroic Sparkling Arcanite Ring; Old Hillsbrad, Epoch Hunter;
http://www.thottbot.com/i28227 Cobalt Band of Tyrigosa; Mana Tombs,Nexus Prince Shaffar;
http://thottbot.com/i29352 Ring of Cryptic Dreams; 25 badges;
http://www.thottbot.com/i29367 Normal/Quest Corrupters Signet; Shaartuul event, possible drop;
http://www.thottbot.com/i32941 Ashyens gift; Cenarion Expedition, Exalted;
http://www.thottbot.com/i29172 Seer's Signet; Scryer Exalted;
http://www.thottbot.com/i29126 Ryngo's band of Ingenuity; Soccrates, Arcatraz;
http://www.thottbot.com/i28394 Band of Dominion; BoE world drop;
http://thottbot.com/i31290 Scintilating Coral Band; Steamvaults, Hydromancer Thespia;
http://thottbot.com/i27784 Lola's Eve; BoE epic world drop. Part of a set with Charlotte's Ivy (Necklace);
http://thottbot.com/i31339 Band of the Guardian; COmpleting Black Morass;
http://thottbot.com/i29320 Enchant: Spell Power (+12 damage). Enchanter only.
None for non-enchanters.
Trinkets Crafted Living Ruby Serpent; BoP, Jewelcrafter only. pattern is KoT revered. Note: cooldown is 5 minutes, while most Trinket cooldowns are only 1.5;
http://www.thottbot.com/i24126 Heroic Icon of the Silver Crescent; 41 Badges;
http://www.thottbot.com/i29370 Quagmirrans Eye; Slave pens, Quagmirran;
http://www.thottbot.com/i27683 Arcanist Stone; Old Hillsbrad, Epoch Hunter;
http://www.thottbot.com/i28223 Normal/Quest Scryer's Bloodgem; Scryers rvered;
http://www.thottbot.com/i29132 Shiffar's Nexus Horn; Harbringer Skyriss, Arcatraz;
http://www.thottbot.com/i28418 Xi'ri's Gift; Sha'tar rveered;
http://www.thottbot.com/i29179 Starkiller's bauble; Quest starting by killing the large Void Waste in Ethereum in Netherstorm
Enchant: None exist
A short note on trinkets: + Spell Hit Rating trinkets are particularly good sources of hit rating, since they can easily be swapped in for boss fights, and you needn't worry about enchants or anything to keep them updated. However, don't forget to swap them in for Bosses, and back out again for trash! *mutter* Like I have on occasion */mutter*
GemsThere are many different types of gems that can be used. These are the 'types' i would recommend, in the order below. Which one you choose depends on what you require, and whether the socket bonus is worth getting (it usually isn't). In terms of the 'rarity' (i.e. uncommon (green) / rare (blue)), I would recommend only putting the rare version in gear you know you will have for a fair while. They are expnsive. I put the 'green' versions in gear I'm not sure I'll use much, or for long, or am testing out various combinations.Note: there is no uncommon version of the Veiled gem.
Gems:
Veiled (Orange) {Spell Hit Rating/Spell Damage} (Noble Topaz)
Runed (Red) {Spell Damage} (Blood Garnet / Living Ruby)
Potent (orange) {Spell Crit/Spell Damage} (Flame Spessarite / Noble Topaz)
Glowing (Purple) {Stamina/Spell Damage} (Shadow Draenite / Nightseye)
Great (Yellow) {Spell Hit Rating}
(Golden Draenite / Dawnstone)
Meta gems: (All but first made by Jewelcrafters. First bought with Spirit Shards in Terrokar Faction base)
Swift Starfire Diamond (12 Spell damage, and minor runspeed increase) {2 Yellow, 1 red. Very easy to manage, very good gem}
Destructive Skyfre Diamond (14 Spell crit, and chance for Spell reflect) {2 of each colour}
Mystical Skyfire Diamond (Chance on spell cast to reduce Spell Casting time) {More Blue than yellow. Difficult to manage, as yellow > blue gems}
insightful Earthstorm Diamond (12 Intellect, and chance on spellcast to restore mana) {2 of each colour}
