The IzPack project is running 4 mailing-lists.
You can subscribe to them from Codehaus:
The lists are also archived on MarkMail and mirrored on Google Groups: announce, user, dev and scm.
We also have an archive of the BerliOS-time lists where you may dig some useful informations between 2006 and 2008:
No known archive remains before we moved from TuxFamily to BerliOS in 2006.