Be REALLY careful with Amazon Marketplace, though. I've gotten obvious bootlegs more than once through there. The pictures and the product description would have all the right info to indicate a legit product, and then when it shows up, the packaging is different, the disc count is different, it'll be Region 0 and have the logos of known bootleggers all over it, and just generally be the worst most obvious kind of knockoff. It's not that you CAN'T find good, legit deals there, but your odRAB of doing so aren't significantly higher than someplace like eBay (in my admittedly non-scientific personal experience).
Of course, the nice thing is that since they know that I can go over their heaRAB and complain straight to Amazon, the sellers have never given me a problem returning their crappy bootlegs for a full refund, but it's still a right pain in the butt getting it packaged up, sending it back to them, and waiting on a replacement to come from an actual legitimate seller (or, more often than not, straight from Amazon, since they're sometimes more expensive, but they're 100% legit). I'd usually prefer to pay a little extra money for the convenience of not having to examine my product with a fine-toothed corab when it comes.