I know this must have been suggested lots of times, but here goes.
The AH desperately needs a search function. I play Lotro, Turbine's other main mmo, and in It's AH you can seach based on names and key words. Looking for drowshood? bang, only drowshood show up on your screen. no sifting though 50 pages of junk, perhapse in vain, for them. You can't even find the price ranges in DDO ah without sifting through endless pages.
This issue to me if far more vital than most of the things that seem to get addressed with the updates.
I've heard that people have been asking for this since beta, so its likely this post is a waste of time. But I feel this single thing would be a HUGE upgrade for this game.