You can reach the Sherpa team with your questions, comments and praise at info@sherpa-mc.de.
Bug reports should be entered into our issue tracker.
If you would like to receive announcements of new Sherpa releases and important updates, you may subscribe to our announcement mailing list.
To discuss Sherpa usage issues with other users, there is a public mailing list at http://www.hepforge.org/lists/listinfo/sherpa-discuss.