Well, you probably have a manufactured PC (ie from Dell, Gateway, Compaq, eMachines, etc) so you just have to go the the website of your manufacturer, type the model # of your PC into the search tool, and you should be able to find all the drivers for your computer. If you have an actual video card (as in PCI or AGP) you can go to
www.nvidia.com, and download the drivers there.
Out of curiousity, how much did you have to pay to get the computer shop to get you your modem drivers, and how long did you have to leave your computer there for them to fix it?