The ati 9600 is around $80, I got mine sometime last year and its not the best, or close to, but it keeps things smooth on my 800mhz peice of $H!+.
If you have a better proccessor and more mem (i'm only at 256meg and it gets awful on loads), It's recommendable as a great mid-grade card.
Although you didn't ask about audio, the audigy se sound card where I live is $30 a pop. If you happen to have the extra pocket change.
P.S. Don't shop at walmart for you graphics cards. Find a pc store for great prices on hw.