Stratford, Ontario-First Sunday of every month from 4:00 on at Bentley’s Restaurant and Pub, located on Stratford’s main street. Tunes played are a combination of Irish, Scottish and Ontario.
London-Third Sunday of the month at 4:00 (alternates with Bentley’s). Located at:
Wit’s End Pub and Grill
235 North Centre Road
London, Ontario
Phone-519-850-9487
The session at the Witt’s End (above) usually goes from 3-5pm.
Edit: But now there is no session there…so if you show up you’ll be all by yourself. 
Session update-
Stratford session has moved to Molly Bloom’s (not far from Bentley’s). Still 4-6ish first Sunday of every month. Darn good session-if anything too much of a good thing, averaging between 10-25 musicians. The atmosphere is very friendly and sociable.
Wit’s End session is on hiatus for the summer. And the Round Tower session is off indefinitely due to a change of owners.
The weekly session in London is now at the Chaucer’s Pub at 122 Carling Street. Check out : http://www.marienbad.ca
Things start around 8pm and go to 11.
Mostly Irish standards yet welcoming to Ontario style, Scotish and old time tunes as well. Friendly bar staff!