I found two court in CDN-NDG, one is KENT, one is SOMERLED. KENT is free in 2008, but it is in CDN. Here it is:
Kent
Free in 2008
3220 Ave Appleton (at Hudson
514-872-1122
May 3 to Jun20 and Aug 30 to Oct10 with reservations: Mon to Fri: 3 to 8pm
Sat and Sun:9am to 5pm
without reservations: Mon to Fri: 9am to 2pm
Jun21 to Aug29
Mon to Fri: 9am to 8pm
Sat and Sun: 9am to 7pm
Telephone reservations: call to reserve a court for the same day or the next day