The scripts we used to build the Gentoo Linux images for Amazon EC2 are now available. You can see what is in our Gentoo Linux image and how we built it, and build your image if you so desire.
The scripts are available on bitbucket at https://bitbucket.org/dowdandassociates/gentoo_bootstrap
A newer tool has been built. This time it is in Java. It is self contained, so you don’t need the ec2-api-tools installed. It is available on bitbucket at https://bitbucket.org/dowdandassociates/gentoo_bootstrap_java/