Does he like me? I can't tell and I don't know what to do!?

There's this guy I've known for almost a year now, and we talk a lot, he always IMs me, and we spend hours talking about stuff. A lot of the time, though, I feel like he's giving out subtle hints that he does like me but I'm never sure. Then, about two days ago, we talking about us (as in the topic was me and him only) and then all of sudden he says that he wanted to tell me completely what his thoughts were but he didn't want to say anything because he was unsure. I tried to ask him what it was but he wouldn't tell me anything except that he wanted for the right time to say something. Then all of sudden, he tries to act like it's nothing even though clearly, it is. I don't know if he likes me, and I don't want to bother him about what's been going on his mind but at the same time, I want to know. What exactly do I do?