Well Amazon can be good to shop at but my brother got ripped off once, he long ago had to pawn his whole Tales of the Crypt dvd collection because he has 4 kids to support and he works a full time job, it was a hard time back then but now he's stable with money and work. However.. he found another collection whole dvd copy of Crypt on Amazon. He bought it and spent a lot of money on it.
Once it arrived, it turned out the menus were wrong and some episodes were missing and he was shocked it was a bootleg dvd. Someone did a hell of a job doing that and he had to contact Amazon to get his money back and he was ripped off, he did get it back and yet he went off and sold the bootleg elsewhere
However you just need to be careful when shopping used things or "new" things if they are cheap. Amazon is still a good place to shop but i NEVER shop PC stuff there, i always stay with NewEgg or Tiger Direct. Well NewEgg mostly never failed me, Tiger never really have good shipping rates.