A lot of questions like this (how to get dates, rise up the ladder, find friends, etc.) have the same answer (well essentially). All you got to do is -
1. Get out there
2. Be yourself
I wrote a whole essay a minute ago, but really it could be a whole course. Like the theme of YCombinator with startups, do things that don't scale.
Find a purpose that you can bring to the table. Can you code well, play a sport, sing, draw? If you have a skill or a hobby then pursue that. I find friends for every activity I do. Its not that I'm trying, but people are everywhere doing everything.
Those people you find in bars aren't always friends since forever either. Life experience tends to make people more emphatic towards each other, right? We all have gone through schools, jobs, and relationships. Had ups and downs. Sometimes its just nice to sit down with anyone who's listening to talk/rant/laugh about those moments.
I'm 31 and work 1hr and a half from home. My house is in a town 2 hours from where I grew up. I knew no one when I arrived but now know plenty of people. And not just in my town, but all over. Some of my favorite people I have met the past couple of years. I tend to see them only once or twice a year. When we do meet up, we can spend all night talking as if we grew up with each other.
If you're open to be a little transparent and also are interested in hearing other people's stories you'll do fine. You'll find it get much easier the more you allow yourself to chill out.
Try this -
If you're really having problems meeting folks try the following.
1. Find any gathering where people would be active in your favorite hobby
2. Give yourself only 10 minutes (you can stay the entire night, but 10 minutes from when you arrive to when you leave is enough)
3. Listen in on a conversation (or join the activity for a session) and add a couple of knowledge here and there
4. Leave
What have you learned? You learned how to find people! You may also have found a couple of people who you ended up hanging out with for the duration of the 10 minutes. You might have even stayed the entire night having fun. You may even have had a few FB invites coming your way.
Remember, most people are usually game for new experiences. You are that new experience. Get out there and have some fun!