There are no books since this is the very beginning of serious homebuilding and experimentation. To be honest I don't think there is any advantage at this time to using LEDs, except for a strong desire to experiment. While they are now working, they have yet to come close to out producing HIDs ( think however, that is very close to happening with SNStealth).

LED arrays can be quite difficult to build and get working right. You need to have at least a basic electrical/electronics background and be able to do light mechanical and electronics construction. I have been spending some time on the "perfect LED" string. One of the guys is having some problems, even though he sounds like he has a pretty good grasp of electronic construction.
You might want to check out the entire string and jump on it with any questions.

There is scattered info on the internet, but you have to have some background to understand it.