How do I become a Christian?

I want to become a serious Christian. I'm young, teen-ish years. I want to find maybe a religious site to help me, where I could write questions and get answers, like this but dedicated to christianity. I feel like I get a bunch of judgemental comments on yahoo about religon. I never go to church, and I barely know what's right and wrong from the mind of a strong, pure, and true Christian mind. I don't even know the ten commandments, or how to repent. I want to go to heaven and do what's right in life. Please, help me find Christ