I've reorganized my archive, so I gathered collections of work by others, mainly made before 2000.
http://www.samshuijzen.nl/sam/arch/e_mods1/e_mods1.html
http://www.samshuijzen.nl/sam/arch/e_mods2/e_mods2.html
These files are not selected on quality, so can show a good impression of what's just trendy crap, and what goes beyond.
Another trail to be is the huge collection at Modland. The links for XM and MOD :
http://krum.ethz.ch/ftp.modland.com/Fasttracker%202/
http://krum.ethz.ch/ftp.modland.com/Protracker/
And, because of the Unix view, check the parent directory as well for other interesting stuff.
very fast modland mirror (http://files.exotica.org.uk/modland/?file=pub/modules/).
When it comes to "oldskool", Amiga Music Preservation (http://amp.dascene.net/home.php) is a very good source as well.