Well, my buddies got me into the sport then I've met a couple on here, met a couple on the lifts, met a couple in the bar at the hill, etc.
By and large though, I just ride. If I can find some people to tag along, great. If not, I'm gonna go ride anyway.
I ride alone often, but I usually end up with a 3-5 person group. Mostly guys I've known forever and some co-workers.