Not heard of anything coming up but I am just getting started. They held a Vancouver homebrew competition this year http://www.vanbrewerawards.com/ not sure if its happening again though. I know they held the canadian brewery awards in september but I think thats just for the pros. Canadian beer of the year was Thor's Hammer barley wine brewed by central city brewing.
The ALES club out of Regina (www.alesclub.com) hosted last year's Canadian Nationals, which was also a regional event for the National Homebrewing Competition. Sometime in the spring IIRC.