http://hem2.passagen.se/c64linus/
Great c64 site with emulators, games, SIDs etc.

http://www.poli.studenti.to.it/ftp/pub/c64/games/?en
C64 game site. About 1000 games.

http://users.dhp.com/~shark/c64music/hv_sids/
The High Voltage SID collection with 8251 SIDs