I sent in my resume online, then I talked with a friend of mine who worked there. He helped as he was able to do something in the resume database to make sure I was called. I was also called separately by a recruiter who found my information on linked-in. This put me in the loop for a couple open positions. It seems the goal of Amazon is to process as many candidates as possible but it's not a perfect system. I was originally targeted for a group that I was not as interested in and wasn't as good a fit for. I told them that I was interested in another team and they were good about putting me on both loops. I think this didn't matter initially, as the interviews are not specific at first.