Church! Not into the whole god thing?
Hmmm.. any friends have any little sisters that are coming up in the world? (18 years old)
How about bars? Not your scene?
Take a class or something at a local community college! no?
Randomly ask girls on the street? Walk away if they say yes, but only for $10
Work? Office romance is usually a bad idea all around, but if you are hard up... what the hey.
www.adultfriendfinder.com? NSFW, and they probably just want your money.
The best advice I can give you is, don't be afraid to talk to a girl. The biggest hurdle most people have is the first step. That first awkard conversation where you want her to know that you like her, but trying not to come off as the crazy-stalker-keeps-her-in-a-pit-in-the-basement kinda guy. Unless that's what she is into... And quit looking. 9 times out of 10 you will find someone when you arn't going crazy looking for company.
But what the hell do I know? Nothing. No one does. There is no advice anyone can give that will work for you.
Be Friendly, say hi, don't act, actually be interested. It's far more important than being interesting.