ebay is great for selling unwanted stuff. The only problem with it is when you are buying, you ave to be careful, real careful. Ive been ripped off once, but managed to sell the item on for more anyway, so it wasnt too bad.
I make my living selling on eBay and have done for the last four years. Most of this house has been decorated with stuff I've bought through eBay but I'd never buy anything that cost more than I can afford to lose unless I take certain precautions, i.e. buy from experienced sellers with high percentage feedback - and (if its an expensive item) contact them in advance to make sure that their account hasn't been hacked. If its over £100 I also empty my PayPal account and then pay through PayPal using a credit card so I get double protection.