You're into gaming That might be a good place to start finding people with similar interests. If you're in college or somewhere similar, try to find a "nerdy" hangout (there's always at least one) and go there between classes. Try playing with others, getting to know them, talking with them about that stuff--LookTwice is right; opportunities do come naturally in college. I've seen real, live, overweight people in real, live relationships. It's NOT that big a deal.
Don't be all desperate and "I want to get a girlfriend" because that won't help you any...You can work on your looks if you want like lost561 said, and keep your genuine personality (if you pretend to be something you're not, people who do start dating you will break up with you quickly when they realize who you really are). You can still be yourself and use good social skills--you can like what you like and do things you enjoy, but still avoid offending people or talking about things that scare them (mostly stuff that comes from human bodies, but also other things sometimes). Do work on temper.
But most importantly, you need to go places--most importantly, places where people hang out and share your interests. Not all public areas are the same (a lot of times Neurotypicals will talk like they are, but that really only applies to people like them who 'fit in' with 'most people'). Keep your friends and find acquaintances. Be friends with females too--you'll learn how to deal with them (they ARE different) and some of them may develop feelings for you, or introduce you to their female friends. But when you make friends with someone, don't ever do it with the expectation of future dating. It makes a hollow friendship.