Congrats! The first person I told was my sister when I was 16. After that I didn't need to tell anyone else in the family because she can't keep a secret.
I told some of my friends (including one I had a crush on) and pretty much everyone was fine with it. The good thing about coming out to friends is that you usually know beforehand who's going to be okay with it. And the ones who won't be, you can just stop being friends with them.
I came out to the rest of the world (i.e. resolved to be proud of and never to lie about my sexual orientation) when I was 18, almost 19. College is a great place to do it.
And like someone else said, it's never going to be as bad as you're afraid it will be. I come from a family of crazy liberals and have a stepmom who leads seminars to educate high school teachers on issues facing LGBTQ students, and I was still afraid of coming out to them.