BizRate:
http://www.bizrate.com/
You'd just have to enter 'digital cameras' where is asks, "What are you shopping for?"
I priced a couple cameras I've seen retail prices for and their prices are quite good.
But, always bear in mind that when you buy online you don't have a camera store to go to for orientation to & training in use of the camera, etc. & if something goes wrong with the camera no one to help with hands-on diagnostics.
Plus it's always good to check out cameras in person and handle them to see the quality pics they produce and if they feel good in your hands and up against your eye (if a DSLR).