Honestly, like many have said here, looks don't matter at all... I work out quite a bit but I'm still pretty overweight and it's never stopped me
Whoever said "Work out" was right on the money. It really does help confidence a lot, makes you feel good, and even makes you look better too! It's not easy sometimes, but after a while you can't live without doing a bit of jogging or lifting some weights twice or three times a week.
What you need to do, and I learned this too in my younger years, is to be less of a "submissive nice guy" and more of a "alpha"... now I'm not saying turn yourself into a complete arsehole, because really even if girls like that I know you wouldn't like yourself inside. What I'm saying is when a girl asks for you to hold her purse while she goes outside to talk to some boy on her cell phone (not that this has ever happened to me before :P) tell her "no". You're not there to submit to her, you're trying to get her to (hopefully) submit to you. BE AGGRESSIVE. Even with female friends you have right now, you can not-so-easily change your status in the relationship in two fashions: 1. Leave for a few months and then meet again, it's like new most of the time. 2. Start doing a bit more physical interaction with them, nothing too insane, but arm touching, massaging, etc. If you make them feel good physically, and suddenly you're not being submissive to them, there is a (miniscule) chance you can escape the friend zone and actually get somewhere. (not saying there is any problem with the friend zone, if what you're looking for is female friends)
Or, honestly, you can just wait. Trust me, any relationship will occur to ANYONE if you just give it time. That's how come even the obnoxious losers you knew as a kid end up happily married later on.
Anyway, I hope my advice either helped, or at least didn't offend. Good luck on your quest for the pretty ladies!