If you need to reinstall your printer or scanner driver -- or want to make sure that it's the most recent version -- then it's time to go straight to the manufacturer's Web site. Many sites will have links right on their home page labeled "Downloads" or "Software" or Drivers." If not, then look for links to their technical support pages, or even to the product information about your device.
If your printer or scanner is more than a couple of years old, you may find that the driver for your device isn't available on the site. Don't despair -- you can still probably find it.
The most obvious way is to contact the manufacturer and ask them to e-mail a copy to you. This, however, depends on how accessible the manufacturer is, and how willing to e-mail a legacy -- read: older -- driver. If the manufacturer of your device is easily e-mailed or phoned, and if they are happy to send you a copy of the driver, then great! you're home free.
However, if you want to avoid waiting for a return e-mail, or holding for tech support, then there is another way. Most printer/scanner manufacturers are international companies, and most have different Web sites for different countries. Many times, a printer or scanner whose information is missing from one country's site can be found on another.
So, for example, if you can't find your HP printer's driver on the United States site, you can try HP's sites for the United Kingdom, Canada, or South Africa. You can try some of the sites for non-English-speaking nations as well -- often, sites for countries such as Japan will have an English-language version. And finally, if the only site that has your driver is in, say, German, you might still give it a try -- you may not be able to read all the instructions in the driver, but it will still work with your printer.
If you're dealing with a very old printer, the driver may no longer be available on the Web, but Windows may have come with it. For example, if you've got Windows XP, check the Add Printers wizards -- your computer may have come with a driver you can use.

