I'd rather not try Ebay. If the phone was reported lost stolen, in account arrears, etc. then my cell phone company won't activate it until the previous account is cleared up. So Ebay doesn't seem worth the potential hassle. I want to buy the phone somewhere where I can return it if there are any problems.
I recently bought one from the Orange website, here in the UK. They offer recons at a low price with a six month guarantee and it was effectively a new phone. Perhaps some of the US companies do the same?