From a veteran. I have tried everything, and I do mean everything. Here are what i consider my favorites.
Clubs - if you share a genuine interest with a girl/woman (be it Chess, sci-fi, or hiking) you have already taken the first step toward friendship
Social sports - bowling, volleyball, etc. if you have the oportunity get some of your buddies and go do these things (co-ed games of course). Have fun, and be seen as fun (don't stand around like a bum and don't ogle over the ladies). Smile if you happen to catch their eye.
Certain types of bars - Interactive dance bars (country, swing, etc.). I know what you are thinking but I met Mrs. CinderElmo at a country bar. Not a Blue-brothers good-ol-boys type of country bar, but the kind where normal people go to listen and dance to country music. You might think I am crazy, but country line dancing and country couples dancing (cha cha, two-step, barn dance, etc.) makes it ridiculously easy to ask them to dance casually and to have fun.
Personal Adds - I know people who have really found some quality women using personal adds. Granted there are a lot of losers, but it at least gives you the opportunity to screen them first.
Closing thoughts; be and act positive. I lived in a distant city with no friends and I still joined clubs, went to bars, etc. and tried to have fun. No woman will come up to you if you are sitting on your couch or even if you go out and still sulk. Self confidence, once acquired, is your most valuable weapon in finding happiness with the opposite sex. If you don't believe in yourself it will be very hard to convince anyone you are a keeper. We all have flaws, but how you project yourself can overcome almost any physical condition (acne, crooked teeth, weight, etc.). At least IMO!
Good luck, hope my thoughts help someone. If not keep trying!