On the "A Cloudy Place" blog there's a recent post about the steps the author ( Shameer) to to get PHP and Git set up on the Elastic Beanstalk service from Amazon.
When Amazon announced Beanstalk’s support for PHP I was curious to know what it would look like. So I decided to give it a try. I hadn’t used my AWS account for a while, so I had to do some account setup tasks, configuring command line tools, etc. In this article I will explain how to set up a PHP application in Beanstalk from scratch.
He walks you through the entire process (complete with some screenshots) of getting the command line tools set up, creating your first PHP application and connecting it to your git repository. There's no database instructions included because the default EC2 instance doesn't include them. You'll need to refer to these instructions if you need that for your application.