Something like this happened to me recently when I was trying to get hold of the Benny Motzfeldt book - ordered it (new, which was a bit confusing) from Amazon, paid for it etc. then got an email saying they didn't have it.
However, I did searches using the ISBN (and had a good bit of help and encouragement from friends here about it) and found a newly listed second hand copy which I managed to buy through Amazon (not too sure how it worked, but it did) and I've got it now. :rah: