I cancelled my last order with Amazon.com
I ordered a bunch of CD's, with the longest "usually ships in 8-11 days." All of which, whilst not mainstream, are not exactly "rare".
To cut a long story short, they ended up cancelling some of my orders after 2 weeks, as they said they couldnt find it, and delayed the shipping times by up to 3 months, at which point I cancelled it. Almost every time I checked my email I was getting news that one of my CD's was delayed.
Basically, they list every product in the world, hence the "worlds biggest selection", but when you actually order things, they dont have them.