Amazon's Product Advertising API

For a while I've been trying to come up with a safe and easy way to catalog my movies. I have quite a few of them and often forget if I have a specific season of Dexter or Psych. This catalog needed to be both easy to populate and easy to view on the go. So I started playing with the Amazon Product Advertising API as it would let me look up movie data on amazon and store it locally in my own database for fast access on-the-go. No typing the actors, movie length, and description. Sounded good to me. Only one problem: I was not familiar with creating the API signature type that Amazon required.