19 and no girlfriend!
Hey, I'm going to be 19 next month and I haven't had a girlfriend for five years.
Before I turned 19, I wanted to have sex and a girlfriend. I really wanted a serious relationship. Since I graduated high school, there aren't any girls around anymore.
I'm kind of geeky so girls don't want me. I don't have any crushes and there aren't any girls that want to date me. I go to the movies with my friend but we can't pick anybody up.
Think about your priorities
If you want sex and a girlfriend, but you don't have a girl in mind, what is it that you really want? If you just want sex, that's one thing, but you said you also want a serious relationship.
If you really want a serious relationship, it's better to start that relationship without thinking about how fast you need to get sex.
Picking up girls at the movie theater is hard. Since you usually don't talk to most of the other people at the movie theater, and you have to be quiet during the movie, it's not the best way to find new girls.
Instead, try joining a local community organization that you have an interest in or volunteer somewhere. It's a good way to meet many new people and plus if you don't find a girlfriend at least you're getting out and doing something you enjoy.
Since you're 18+, you could also try using personal ads. Yahoo Personals (www.yahoo.com/personals) allows you to post ads for free, and on Craigslist (www.craigslist.org), the people are a little crazier, but it's free to both post and reply.
I know it's tough being single, but you just have to be patient... trying to set a goal like "heave sex before I'm XX years old" is really just hurting yourself.
If you want a long-term relationship, you want someone you are a good match with, and the best way to find that person is just to get to know as many people as possible and keep your eyes open.