Ahh you've grabbed my attention.
I was gonna stop posting for a while but this is just too similar to how my current girlfriend was.
Here's the low-low:
1. It'll be HARD to get her to open up.
2. You'll doubt that she likes you, because she's so shy.
3. Things will be awkward for a while after you start dating, until you build some serious rapport.
But, when she does open up... it'll all pay off. Seriously it took like a month and a half before my girlfriend and I became really comfortable together.
Like Alkali said, treat it as anyone else... it's just gonna take longer.
I just gave you some of the things you will notice, but not to worry about.
Good luck man