1. Get a friend's permission to "hack" into his Amazon account (or "hack your own account").
2. Contact Amazon's customer service, try the same social engineering techniques that the OP documented.
3. Once you obtain some sensitive information from the account, scare the CS rep by saying: "Haha! I am actually not the customer. I am a journalist/hacker/whatever and wanted to see how easy it was to social engineer information out of your customer service department, and you failed. I would like to talk to your manager please."
Hopefully if enough people do this, it will get some internal attention at Amazon.