It was a risk you took, and you do indeed sound like an idiot, but its ok.
Here is a list, of performance in that range.
Good
GF FX 5800 Ultra (5800++)
GF FX 5800 (4x2, 128 bit)
Radeon 9500Pro (9700 w/128 bit memory)
Radeon 9600XT (Pro++)
GF FX5700U (5700++ - Note - superior performance to 9600XT in non shader limited situations)
Radeon 9800SE (4x1 software crippled, 256 bit, can be modded to 9800)
Radeon 9800SE (128 bit, can be modded to 9500 Pro)
Radeon 9600 Pro (9600++)
GF FX 5700 (4x1, 128 bit)
------- If you are buying new for a somewhat modern computer, going below here is not recommended if people will be playing games more than occasionally on the computer.
Expect to pay $110-170 for cards in the medium performance range for DX9 stuff. Don't bother with the more expensive ones in the medium speed range because you can get a fast card for a similar price.
Fair
GF FX 5600U v2.0 (5600+++)
Radeon 9500 (4x1 (software crippled from 8x1, can be modded), some have 128 bit memory, others have 256 bit memory, 256 bit models can be modded to 9700, 128 to 9500 Pro)
Radeon 9600 Pro "Lite" (9600Pro--)
GF FX5700LE (FX5700 running at SLOW clockspeeds - potential for OCing is huge)
Radeon 9600 (4x1, 128 bit)
Radeon 9550 (Radeon 9600-)
FX5600U rated so low because of bad DX9 performance, it would be better if that didn't count.
Starts around $75 for 9600 nonpros (9550s should start around $65 and would be viable for mom's computer)