In linux, most drivers are included with the kernel, it is unusual to install external drivers.
If you should need non-free drivers, then you go first to the distro repositories and look there. Typically, forums can locate 3rd party repos for questionable material.
To check your installed hardware, it is seldom any use to go by the manufacturer specs alone... open a terminal and enter "lspci" (sans quotes) and look for what it says there. lshw can be useful too.
ATI Radeon Powercolor 9600 Pro;
... looks like this is supported by the free software "radeon" driver. (RV360 chipset?)
Dlink DWL-G122 RevC
... this is a wifi usb adapter which is a notorious lemon
- even in windows. I'd buy a different one. DLink have a gpl driver for it, known to be a pita - but maybe a better version is in the kernel by now?
You can try:
... this looks like a standards compliant PCI ethernet adapter to me, should work out of the box.
Create SB Audigy 2
... soundcard: it's reported working out of the box with alsa.
So... that's everything but wifi.
The wifi link suggests ndiswrapper... which you can get with your windows box and sneakernet over. Then you can use the windows drivers. Did no more that skim the thread though, maybe it didn't work for that guy in the end neither