Recently I started using Ubuntu to develop and carry out some tests with the Flash Platform, I came across the problem of installing Flex Builder on Linux. After some tests and almost giving up, with the help of my friend Wenderson, could solve the problem.
Follow the link for the article detailed how to install Flex Builder on Linux using Ubuntu distro.
http://www.wendersonsouza.com.br/index.php/2009/10/03/usando-flex-no-linuxubuntu/