3 associations come to mind.
www.bowhunters.ca (Alberta Bowhunters Association), the
www.fca.ca (federation of canadian archers) and
www.3DAA.ca (3D Archers of Alberta). The ABA has a provincial championship and the 3DAA has a tour shoot system.
As far as rules go, both associations follow the Canadian governing body which is the FCA. The rules can be found on the FCA at
http://www.fca.ca/rules/WEBFCARules2006.pdf
This is the ENTIRE rule set for all disciplines, I think you can just skip most of it and go to chapter 11.
Please don't get wrapped up in the regulation of the sport, the idea is to have fun!
so to condense the rules that you really need to know as a 1st timer,
1. part of your body needs to be touching the stake, your equipment class will determine which one. Basically if you're an adult male with a compound it's the red/orange stake. If you're an adult female with a compound it's going to be the green one. (cubs, youth, trads & seniors all have different stakes)
2. no discussing yardages before everyone has shot the target, and not while a following group is within earshot.
3. arrows need to be touching the outside of the line to be scored.
4. only one arrow shot per target (unless the club has set up different rules)
When it comes to equipment classes, basically your hunting bow is usually in the bowhunter release category. There's some twists to that but that's the rule of thumb. When in doubt ASK!
Now the most important rule of all
HAVE FUN!