Based on Dave's PM, I looked for things to do on a Thursday, and found:

sessions:
- an Irish session at Dora Keogh, which is a pub in Eastern Toronto, accessible by subway.

- concerts:
Free Times Cafe, which is downtown, will probably have a show on but they don't have their schedule posted that far in advance. Hugh's Room, which is a restaurant/folk concert venue in western Toronto (accessible by subway) has a show that night by Andy Irvine, who I'm not familiar with. The Tranzac may have something but right now there's nothing up on their schedule for that day; none of their ongoing participatory events are on Thursday.

- open stage:
Renaissance Cafe, which is in Eastern Toronto and reachable by subway. It looks like they haven't updated their website for a year but I think this is still going on. Let me know if you're considering this option and I'll confirm it. Don't expect there to be much in the way of traditional or tradition-based music, though.

I still think coming over to my place for supper and singing is your best bet...

Marion