I like to use
www.NEXTAG.com
For instance..................don't even go to all the sub-catagories, just type in say....a certain model number of something or a brief name of what you are looking for and see what happens.
Also...I'll use
www.Bizrate.com sometimes and there's even
www.Pricegrabber.com
But I've just gotten used to using Nextag mainly.