Do you want reading materials on AG brewing or do you want reading materials on how to build a system?
For AG,
How to Brew (buy it, the free online edition is great, but has been significantly updated) Designing Great Beers, Radical Brewing, Brew Like a Monk (BLAM is IMO one of the best researched and written style books out there, well worth owning if you ever want to brew a Belgian), and Yeast (haven't read it, but its the only book dedicated to understanding yeast for the homebrewer so if you have questions on that, a definite read).
For building a system:
Brew Ware (I haven't read it, but would probably put in the right direction). However, more than anything I would do some research on this forum to get an idea of what you want and then ask questions and folks will be more than happy to help you with your build.