ha..you're over thinking things I think..
How do you talk to anyone? Think about the last time you had a conversation with a random stranger and ask yourself how it started. That's how you (personally) meet new people..and that's how you should meet girls (or people in general).
Don't focus on the fact they are a girl (so are 3 billion other people on this planet, they aren't that special..) but more on their personality. Just get to know them as a person.
And..if all that fails..practice. Just go up to a girl ( a girl who you have no intentions with) and say hi. Ask her a couple questions..and depart. You'll find that this gets easier with more people you talk to. If girls are too intimidating..then do it with guys first. Or even online on chat sites..just start talking to people (anyone and everyone) and eventually you'll be able to meet anyone you want to.
you'll never learn unless you try saying hi at least
just pretend its a guy like a guy friend and talk to them.
its not realy hard its easy just think of them as a human being, how do you talk to your mom? lol