If the 6800GS is too expensive, the 6800XT is an okay card too (~$125). It performs pretty poorly next to the 6800GS though (~$175). Look at the 7600GT too, it's better than the 6800GS by a fair amount and just below $200.
yea i glanced at the 7600, it looked crappy for the price, i might sell my ipod video for $180, i know its cheap but i bought it for $200, so i might be able to afford the 7800 gt