After a rather rough upgrade from Lucid to natty my source list has been out for weeks. The prospect of going through and finding all the correct replacements, including third parties was just too much.
Today though I stumbled upon this :- http://repogen.simplylinux.ch/
Select all the sources you need, hit generate and bobs your uncle. Just remember to back up your old /etc/apt/sources.list before applying the new one.
