If you have info on these people and they are on this forum, go to the scam accusations thread and create a scam accusation!
When I think about it, you will be better off with moving this thread completely to the scam accusations thread. It will be more visible there and some more experienced users that have already dealt with Amazon gift cards will be able to help you. I have no experience whatsoever with these cards.
Here is the thread and good luck with sorting this out!
https://bitcointalk.org/index.php?board=83.0