Get this one. It's excellent at gaming:
ViewSonic VX922 Black/Silver 19" 2ms gray-to-gray (avg.); 2ms white-black-white (typ) LCD Monitor 270 cd/m2 650:1 0.294mm Pixel Pitch - Retail
http://www.newegg.com/Product/Product.asp?Item=N82E16824116375
The funny thing is the price has gone down significantly. When I bought this monitor, it was like in the upper $400 range with all the shipping and taxes. It's way good with pretty fast response time. Samsung models are pretty good too.