Of all the lower mainland fields Panther has by far the most people going there to play airsoft. On a good weather weekend you tend to see 60-80 person games on Sundays and 30-40 person games on Saturdays. RIP has their Thursday night games, though they conflict with Panther's Thursday night games, so both groups end up being not as big as the weekend games.
As for guns, I do agree that renting a gun is a good start, there are players who will rent out quality gear for a reasonable price, or Panther rents out their stuff. The local forums generally aren't as busy as ASC, but if you're looking for rentals/rides they are far better to post on than here. You'll find only a handful of the local players browse ASC on a daily basis.
If you do look to buy for CQB you may have some trouble finding a gun that fires slowly enough stock, since Canada's import laws restrict guns to above 366 fps. But with the help of a local gun tech you can swap the spring out for CQB if that's what you'll primarily be doing. I'd recommend looking at a King Arms Metal M4, fantastic gun on a budget. Sorry we can't tell you where to buy until you're AV'd though.