The artisan enchanting trainer (the one you need for 150-225) is located in the Tower of Azora, which is about halfway between Goldshire and Three Corners (I'm assuming you are Alliance based off your signature). Take your favorite travel method to Stormwind, head southeast out the gates to Goldshire, and then follow the road east. Once you see the tower, veer off and head up to it, and go all the way to the top. The artisan enchanting trainer is there. There's also a couple of other miscellany npcs, a vendor of some sort and a quest npc of some sort I believe.
edit: Just in case you're not Alliance, the Horde artisan enchanter is in Sun Rock Retreat, up a hill just to the northeast of the town.
Edited, Sun Apr 16 05:12:27 2006 by GDSlemons