I used one called Doba.com. I WILL NEVER USE THEM AGAIN - THEY ARE MIDDLEMAN. A good source to use is Albany Distributing. Their site is http://www.albanydistributing.com. I have been using them for over a year now and been completely satisfied and their prices are MUCH, MUCH, MUCH better than Doba. Doba’s prices are going to be higher than anyone. I actually believe that Dropshipdesign and Albany Distributing is filling orders for Doba. Just stay clear away from Doba. I hate them!!!!!!!!!!

In any event if you’re just starting up or already established, Albany Distributing is real good one. You’ll gain on their $3 shipping on every order regardless of size and they ship with Fedex.
I use them for all kinds of electronics and appliance products. I think in their last data file they had well over 11,000 products.
If you want over a million items, dropshipdesign.com will have everything just like Amazon. I know their feedback is exploded all over the web, but they are legitimate. You’ll just want to compare prices because Albany winds up being cheaper. Signing up and comparing prices is the best thing.
Another benefit of dropshipdesign is that they will offer you tools to automatically add your items to ebay which I love.
They have a setup fee I believe whereas Albany charges nothing to resell their items.

Here are the sites and both are validated.
www.DropShipDesign.com they are legit I checked them with Seattle Corporations.
www.AlbanyDistributing.com they have an A+ rating on BBB as well which increased my confidence