Gay bars, college groups, county/town groups (even my small hometown county had one of those but they were mostly very old people, but youth involvement in those things had to start somewhere).
It's a bit hard to say since I don't know the kind of area you're in. Even with what I can suggest, sometimes they're completely useless. For instance, I've mostly lived in towns that don't have gay bars, and my hometown had no resources for queer teens. I only really started dating once I got the fuck out of there.