Really weird situation?

So my brother told me about one of his friends that likes me. I like him too but here's where it gets complicated, we've never talked to each other. We saw each other once at a ceremony. so now i find out he does like me and i know his myspace and his AIM but only cuz of my brother but he doesnt know anything about me. my brother was gonna ask him to come to a water park but then he asked if i was gonna be there (i was) and my overprotective brother told him he didnt want him to come even though he says he wouldnt have a problem with me datin him. so how do i start talking to this kid i mean it would be kind of weird to just be like hey i like you. i mean we dont even know each other and if i say hi i dont know where to go from there. what should i do?!