Automated Deployment & Management of Tomcat e-Commerce Site

I like to build a script to install, deploy and configure an e-commerce site. It runs on Tomcat 7 using Apache w/ a proxy load balancer. It uses MS-SQL and MongoDB, and all static files are in Apache 2.2. We are continuously doing new builds and adding new Tomcat instances. We like to automate it as much as possible, and also minimize site downtime while upgrading to latest JARs. Currently we are running on Windows, but like to migrate to Linux eventually. I'm open to using Chef or Puppet. Ideally you are also familiar with AWS EC2, etc. Final price to be determined based on your proposal and scope of work. We like if you use skype.