I also recommend Swappa, I know several people who have bought and sold devices there and no one I know has had a bad experience. And that is saying something, because if you knew some of the people I know... :wink:
Swappa is great, I've used them a ton. Our sister site, Android.net, also has a "classifieds" section where we allow that kind of stuff. However, our guidelines do not allow discussions like this over here. I'm going to close this, edit the OP, but leave it for info purposes.