Consider the root datum $(X^*, \Delta,X_*, \Delta^{\vee})$ of a reductive algebraic group, where $X^*$ is the lattice of characters of a maximal torus, $X_*$ the dual lattice (given by the 1-parameter subgroups), $\Delta$ the roots, and $\Delta^{\vee}$ the coroots. See http://en.wikipedia.org/wiki/Langlands_dual for some description.
Is there any book (or lecture note) that contains some pictures of the root datum of some Lie group $G$? In particular, I am curious if there are pictures of the root and coroot, character and cocharacter, weight and coweight for the case that $G=SL(3)$, or dually $G=PGL(3)$.
