I hear volunteering works great, if you aren't in school. If you
are in school its pretty obvious - talk to classmates, meet their friends, etc.
A big part of it is being a respectful, genuine human being. Also, like
puppychow said, take a risk or two
I don't really have to worry about putting effort into meeting women, because I'm very involved with the cooperative movement in Madison, WI. I live with more than half a dozen women my age and work with many more, I see them in the political activities I participate in and so on.
Plus, if you live in a nice (read: midwestern
) town, you can usually just smile at someone, and if they smile back you know you can be like 'so, you lookin' at those avocados? I love making guacamole' and if nothing else you've got an exciting conversation