Girls/Guys: Can you help moi?

I would really like a girlfriend, but there's no one that I know that I'm interested in. My mates all have girlfriends, so I kinda get left out a bit, and one of them is always onto me to get one. The only I can get one is to find one publically, i.e. try and chat to girls in town and get their numbers and such. The day before, I always say to myself I will start talking to girls in town, make good conversation, but when the time comes, I never have the confidence to. Has anyone got any suggestions as to what to do? I promised myself I'd get a girlfriend before Christmas..