For 1): Chapters 4-6 (this is a single bound text) of Bourbaki's *Lie Groups and Lie Algebras* is often said to be the most comprehensive <s>introductory</s> basic treatment on root systems.  Much modern work in linear algebraic groups and related finite group theory makes reference to it.  

(In fact I have heard it said that this is the high point of the entire *Elements of Mathematics* series, though this is obviously a matter of taste.  For my part, I believe I currently like *Commutative Algebra* the best.)

For 2): apparently yes.  See e.g. [here][1].

[1]: http://math.uga.edu/~pete/Can06.pdf