For starters, here's links to some Toronto folk & folk-friendly venues & events:

http://www3.sympatico.ca/flying_cloud_folk
http://acousticharvest.cjb.net
http://www.hughsroom.com
http://www.mariposafolkfestival.com
http://www.thefreetimescafe.com
http://www.harbourfront.on.ca/noflash/perfarts/music.php
http://www.winterfolk.com
http://members.rogers.com/jeremiah-mccaw/ClubListings.html

For general info try:
http://www.northernjourney.com