Windrivers.com claims to be the #1 Resource for Windows Support/Drivers. If you can't find drivers for your video or sound card anywhere else, you might find it here:

http://www.windrivers.com/

Microsoft Hardware Compatibility List web site has drivers for a large variety of video and sound cards available for download. Please keep in mind that many times these drivers are not the latest drivers. You should go to the manufacturer of your video/sound chipset to look for drivers before using these drivers:

http://www.microsoft.com/hcl/default.asp

Winplanet has all kinds of information on Windows, including a section where you can download drivers from various video and sound card manufacturers:

http://www.winplanet.com

The drivers section of Winfiles.com is an excellent resource for finding drivers for all kinds of peripherals including video and sound:

http://www.winfiles.com/drivers/

Although this really isn't a driver site, follow the link below to Microsoft and their DirectX web site. From here, you can download the latest version of DirectX.

http://www.microsoft.com/directx/default.asp