The LAME Mailing List
Thanks to Jan Peman for running the mp3encoder mailing list for several years!
In September 2000 the list was moved and started being run by Warren Toomey. But sometime in 2011 it got deleted from the list server, so it seems to be gone for good now. You can still peruse the archives though (check the contact page for details).
The development list is run by SourceForge