So everyone says go talk to him. That's good advice, but I bet you've done that anyway and that's why you're interested in him.
How do you tell if he's interested back? Pay attention to him. Does he try to spend lots of time hanging around you, even if he doesn't speak much? Do you often find him looking at you when he thinks you won't notice? It's strange to think of, but that's probably him "making his move".
So! Now you've noticed that he's doing all the right things and giving you a lot more attention than he does anyone else. How do you get him out of his shell? Start holding his hand in the middle of a conversation. (Touch him in any affectionate way, really.) If he can keep from running scared, give it a few minutes, then kiss him. A friendly peck on the cheek, perhaps, or an even friendlier peck behind his ear or on his neck.
Keep your eyes peeled, and good luck.
