How to find out what this guy wants?

Okay then, I have a REALLY bad crush on someone. He's one of my classmates brothers and it all started in school when he started slapping my butt and touching me on my arm and stuff, whenever I'm forced to walk past he either stares (unless I look at him), checks me out, or ignores me. Whenever he is with his mates they laugh when I walk past. He does this to other girls too except he picks on me more. I am so confused, I don't know if he likes me or doesn't, I'm too scared to get his msn addy, I don't want to seem desperate. What should I do?

I know, I hate it when that happens. you really like a guy and they mess with u, but then they mess with other girls, too. Argh! Is this a male strategy to torture girls?

Do what I do; return the favor. Mess with him, check him out all obviously, but mess with other guys just as much. When you do it and you can tell he's looking, give him a look. Maybe wink. It drives them crazy when they're in the dark.

getting his msn isn't beind desperate it just shows your confident and you want to know what's up.
if you like him than go for it.
I would.