Groups is an important point I think, preferably based on a common interest. I'm fortunate in that I'm a tabletop gamer, and as it's an inherently social activity I've always been able to find a roleplaying games group or club wherever I've moved.
I'd be interested if there are any other hobbies or interests that have a similar built in social component?
Poker! I had an awesome group of poker friends in SF, maybe 10-12 of us who'd play regularly, although on any given weekend it'd only be 4-8 who'd show up. We'd sit around a table playing poker for hours and hours, and after half a year, we were pretty close!
I'd be interested if there are any other hobbies or interests that have a similar built in social component?