If you search the serial numbers and model numbers of the hardware you are trying to install, you should be able to find the updated drivers without a problem. Try a search at the manufacturer's home page first -- they will probably have the software upgrades available for free on their site (they want you to be able to use your hardware, even if you upgrade your OS beyond that which is covered by your original drivers -- it makes good business sense to update these for free for you. If you cannot find the new drivers on their site there are still a few options ...
1. You can try the Microsoft sire. Generally they do not store the drivers for every piece of hardware that could have issues with their new OS ... but a lot of times they have links to the places that DO keep the drivers.
2. There are several programs that will automatically search the web for your updated drivers. Run a search on Google and you can find one easily enough.
3. Use this link : http://pcsupport.about.com/od/driverssupport/tp/windows-7-drivers.htm
... It connects to a page with an alphabetical listing of company web sites with Windows 7 upgrades for their products.
There is a possibility that your hardware is not, and will not be supported by Windows 7 (I have some really old video hardware that is no longer supported by Windows in any form). If this is the case, you can buy new hardware to match your OS, or you can change your OS to match your hardware. For the system I use that has the OLD (7+ years old) video hardware, I changed my OS to Puppy Linux. This is an operating system that is designed mostly for older hardware. This is the more complex solution, since you will have to learn a whole new operating system, but in the end it is worth the effort (Linux is known to have less virus problems, and is "open-source" which means that you can change anything and everything that is not perfectly set up for you once you learn the system). There are LOTS of options for linux operating systems ... and you would have to choose which works the best for you ... but they all have small programs that allow them to work Windows hardware, but it sometimes takes a lot of effort to get everything set up properly. If you have a linux-savvy friend, life could be easier ... if not, and you are not GREAT with computers, this might not be the option for you.