I have bought a used mountain bike on ebay, and a new road bike frame/fork. Both were from small LBS dealers. Both experiences were positive ones. I have also sold a bike on ebay (expensive tandem), and that also went well. I'm getting ready to list another bike on ebay today, in fact.

Generally, if the seller has good positive feedback and has been around awhile, you're not going to get scammed. Lots of photos (not from manufacturer's site!) are also very helpful as they you know they actually have the bike in hand. It's good that you did your homework ahead of time so know what size you need. One thing you may want to do, like someone else mentioned, is just establish contact with the seller. If he doesn't have all the bike's measurements listed on the website, have him measure the top tube or something. That both establishes contact and ensures that he is the communicative sort, and ensures that you are getting the size advertised. The only thing that *might* have gone just a bit "wrong" with one of my purchases is that after measuring it myself, I think the frame I got may have been one size larger than it was listed as, but thankfully, it still worked for me.

It will probably be just fine. Breeeeeeeeeeeeeeeathe! And let us know how it all turns out!

Emily