Go here:

http://www.ibuypower.com/ibp/store/configurator.aspx?mid=182

Give the pc 1GB of ram and a 7600gt, and it will be able to play FEAR. ibuypower.com is the best place to buy pcs other than building your own.

For the sub $100 range look for the 7600GT. My friend has one and he can play bf2 on high at 128x1024 @ 40-50fps. theres really nothing better than the 7600GT for under $150 so you'd have to dish out about $155+ for a 7900GS, X1950pro, or x1950GT. At about $175 you can get a Directx10 compatible 8600GTS. anything after that wouldn't be considerd a cheap card :P.

Hope this helps.