Most of the time, you can get that information from the manufacturers. They are typically more than happy to provide whatever pictures they have. After all, you're trying to sell their products.

Doing it yourself: To get the nice clean white-background professional look, you need professional lighting. Depending on the size of your products, you can get a 'home tabletop photo studio' to do your photos in-house (available here: http://www.hammacher.com/qsearch/default.asp)