Re: 25 year old virgin
Listen to Kleeblatt about getting out there and LiLou about being more forward. Both are very right. I volunteer a lot and there's really no better way to meet people. It' a ready made excuse to talk to girls without any awkward introductions or icebreakers which is what a lot of people (guys and girls) have trouble with. Plus doing something good should build your self esteem which is a must. There is literally nothing more important that self confidence!
Also, you have to let them know when you're interested. If you're just standing back and being polite, they might think "oh he's cool" and then go back to paying attention to the guy who's being the center of attention and making all these forward jokes. He may seem like an ass too you, but in reality he's just being fun and funny which is what girls want to be around.
It really does just come down to confidence. If you stop putting girls on a pedestal and start thinking "I'm awesome, they'd be lucky to be with me" then you can start to come out of your shell and be the center of attention and not give a fuck what they think, then you'll be more fun to be around and girls will want to talk to you and you can move on from there. Just don't get too cocky. That's a big n-o. I don't think that'd be a problem for you though.