They're not a part of archive.org (just a totally separate group with similar interests, lead by Jason Scott). The specific project page is here: http://archiveteam.org/index.php?title=SourceForge

The best place to pop in is probably on IRC. For the Sourceforge project it's #coldstorage on EFnet, http://chat.efnet.org:9090/?nick=&channels=%23coldstorage&Lo... for the web client. Though note, the ArchiveTeam project seems to be paused right now.