If you need a device driver that is not included in your Windows CD-ROM, and not available from Windows Update, the first place to search should be the device manufacturers Web site.
If you still cannot find it, consider using DriverFiles.net. I quote from their site:
"On DriverFiles.net we aim to aid you in your search for the device driver you need. This we do completely free, we don't require registration and you don't have to pay an annual fee to be able to download our drivers (most other driver resource sites do).
Some of the drivers on our site are served by an excellent driver resource site - driverguide.com. If you want to download these drivers you'll have to register with them for free."