I started a thread roughly a month ago on this very topic, and many here recommended steering clear of 22" LCDs, mostly because they use TN panels...which have good response times for gaming, but sacrifice color, viewing angles, etc. Quite a few of the posts in that thread caused me to reconsider either going 20.1" or 24".
If I go 20.1", it will probably be the NEC...if I go 24", probably the BenQ, Samsung or Dell...just waiting to see what happens on 24" pricing in the next month or so.
Gaming LCD thread
If you do decide to go 22", from what I saw, the LG 226W and Samsung 226BW are the best of the 22" crop, and fall well within your price range.