I just bought on on eBay. My advice is to buy one that has AppleCare only - and make sure that the seller is reputable or that there is a return policy. You can find a good one on Craigslist too, just make sure you deal with a cool person. By cool I mean you can tell they are actually human, and are willing to sit down with you so you can inspect the unit. How much are you willing to spend and what kind of work are you going to do with your Macbook pro? Any reason why you want an i5 versus an i7?