General
https://www.modplug.com/
https://www.united-trackers.org/
https://www.maz-sound.com/
Applications Anywhere:
https://sound.condorow.net/
Module Collections
https://www.modarchive.com/
Specific Software:
https://mikmod.darkorb.net/
https://modplug-xmms.sourceforge.net/
https://www.soundtracker.org/
https://www.voyager.co.nz/~guyat/index.html
https://petra.hos.u-szeged.hu/~pilu/
Newsgroups:
alt.binaries.sounds.mods
alt.music.mods