First, check out these tips and guidelinesGetting startedLet the bidding beginPayment and deliveryTips for smart biddingPlaying it safeAuction sitesPlaying it safe Despite the potential for abuse and scams, online auctions - even the person-to-person variety - are generally pretty safe. That's because dishonest operators attract a lot of attention. Auction sites and regular users spend a lot of time tracking down and keeping out the bad guys. But you can still get scammed if you're not careful.
A few basic tips:
Determine the seller's reputation. Most person-to-person sites have some sort of peer review system - check with former buyers to see if the seller has a history of good or bad dealmaking.
Make sure the auction site you're using keeps accurate files on users. eBay requires members to have a traceable e-mail address. Anonymous Web-based addresses must be supplemented with credit card information. It's a good policy, and tends to keep people honest.
In a person-to-person transaction, call your seller to cement the deal. Most sellers provide a phone number, and that's a good indication they're on the up-and-up. You can get a much better sense of a person on the phone than through e-mail.
Use the peer review system. This type of cooperative open-market policy only works if buyers provide feedback. If you had a good experience, say so. If you didn't, definitely say so!