How do I get him to talk?

Just talk to him, really. Find something he likes, something he's passionate about, and talk about it.

90% of all communication is through body language. You guys really need to get something together, if he is being timid of asking you out, you should just do it. You know him more then me, but if he is a shy and timid person, there is a least likely chance he will have the balls to ask you out. It could be something relatively simple, if you are a student, call to do homework together so he can keep you company, or just get a cup of tea/coffee at a store before you head to do other stuff.

Usually then it doesn't matter what you guys talk about, I mean if you are really desperate you can bring a paper with you to the coffee house or surf the internet and talk about stuff that is strange in the news and get each others opinions. Kind of hard to encourage shy people to be assertive, especially if it is new to them, so you have to hold their hands to some extent.

Okay, I've been here done this! The easiest thing to do is to first re-mention something light, funny & non-serious that you've texted about. Say "Hey" and follow it with "Did you see xyz? That's what I was telling you about!" It can be anything. Just something to get the conversation going. He'll probably give you a one word answer. (He's scared silent because he WANTS you to like him so bad!) Just smile very sweetly at him and try to keep talking. Ask more serious questions next, referring back to texts if possible. (ie: "I heard someone mention this new song, is that the band you were telling me you liked?) From my experience it's best to steer the conversation in the direction of HIS interests. Music, sports, whatever he likes. That way if his friends ask what you were talking about he can answer honestly - sports - and not have to deal with any teasing from them. Trust me, he'll think it's cool on a dozen different levels. Plus it never hurts to know what he's in to with Christmas coming up!

Text him later and mention your conversation. Say "It was nice to talk to you. I'm usally pretty shy but I feel like I know you and I enjoy our conversations." This will let him know he's doing great and that it's okay to talk to you more. He really needs that confidence boost.

Remember, SMILE AT HIM EVERY TIME YOU SEE HIM! I know it can be hard but this really helps guys a lot!

ohh since you guys just started talking last week, I'm sure you guys still have loads more to talk about really. I don't know what you know about him. but lets say he's into sports, music, games, or anything particular, ask more about them? but ask because you want to know, don't ask for the sake of asking.
btw I'm like you I prefer shy guys than talkative guys they tend to be more mysterious =p

hmmm... maybe do more things with him. words may come out naturally. eat something different... go sumwhere else... do new activities. since you said uve talked about everything when getting to know people, I'm sure there's something deeper to talk about on a lot of topics? have you guys talked abut goals in life? if so, talk more about it? talk more about serious stuff perhaps?