I would like to know everyone's opinion on the best tools for setting up a continuous integration, test and deploy infrastructure for a Ruby on Rails web application API in the Amazon EC2 cloud and any tips or best practices for Jenkins, JMeter, RubyMine, git ...
You can try Railsonfire (Full disclosure I am one of the founders)
We provide Continuous integration and Deployment for Ruby apps as a Cloud Service. Simple setup in < 2 minutes. If you need any help setting it up write me an email to firstname.lastname@example.org, a tweet to @Railsonfire or use the olark chat box at the bottom of our site.
If you do want to use your own EC2 instances I would recommend https://github.com/defunkt/cijoe
as it is easy to set up and run. Jenkins is imho bloated, especially if you want to run ruby builds
I think ci-infrastructure is what you are looking for. "Getting a fresh Jenkins server set up is kind of a pain and because of that, fewer projects have one than should. This project is designed to make it easy for people to fork and get set up with their very-own Jenkins server in the cloud because CI is awesome. "