I always check ebay first when I want to buy something but everything is not really cheaper on ebay. It's cool for somethings
There are much easier ways to find out what's selling on eBay than by asking a bunch of webmaster losers Sign up with eBay's Developer program and use the API to find out what's REALLY selling on eBay. e.g, http://developer.ebay.com/DevZone/javascript/docs/JSDocs/logical/FindPopularItemsRequestType.html
The API isn't a lot of fun to work with, but once you work it out, it's a gold mine of information. Good luck
to tell you the truth, I never bought anything from ebay before for my whole 15 years internet experience!!