Here's a simple guide to use Steve Kemps xen-tools package for Ubuntu (originally developed for Debian).
Read it here
This is the page for anykey solutions xen-tools package for ubuntu.
We used the excellent debian packages from www.steve.org.uk and made minor changes to them to work with ubuntu.
xen-tools is a compilation of scripts made by Steve Kemp to make your xen experience seamless and cogent.