Head on over to Ottawa Valley Airsoft ( http://www.ottawavalleyairsoft.ca/forums/
). They are the "last forum standing" so to speak.
Unfortunately the airsofting community in the NCR went through a collapse the last few years, however there are still plenty of players out there and a few fields in driving distance, but none local.
I was out in Kingston/Ottawa for the last ten years; what sort of "league" are you referring to?