If you need a girl...

If you need a girl actually go up and talk to her first without stupid pick up lines. You'll be surprised at the effect.

What Kami said. Pick up lines can work and all of that but a lot of girls are also tired of pickup lines and sometimes even if they aren't tired of them when they expect a pick-up line sometimes not pulling out a pick-up line can actually make more of an impact because it shows that you are more interested in them then you are in picking them up if that makes sense. Now I don't really have much experience with picking up girls or dating or any of that but I do have a lot of experience when it comes to talking to girls over a variety of subjects and watching people and how they react. It all depends on the person but you might be surprised. It's like going to an NSFW server. You always see a bunch of thirsty guys but believe it or not sometimes the people who are just chilling with the girls will actually end up getting something more often than the thirsty people even if the thirsty people are hot.

What Anime kid said and well just talking with them about anything you find interesting?? If they aren't into the Convo then would you really want that woman to be yours? Trial and error really.