I have asked guys out before and their first reaction is always really confused. They don't expect a girl to ask them out but it's more "wow this is cool" than "ewww freak!" :) do it, then you'll have an answer from him. Just let him react how he will. You win some and you lose some but it's always worth the risk. Either you get a boyfriend or you can move on and find another guy to like. Hope this helps!
Im actually going to be doing this on Sunday when I see him around work. If I can do it, you can. I've already told myself I don't care if he responds negetivley or not the way I hope. It's not like I'm going to know him for the rest of my life, that is if things don't go the way I plan ;p