Which book?

[jeff mutonho]

Kito Mann's Java Server Faces In Action or
David Geary and Cay Horstmann's Core JavaServer Faces?

[Daniel Rhoades]

I learned JSF via "Core JavaServer Faces" it got me where I am today! It doesn't cover JSF 1.2 though being published in 2004.

[Ronald Johnson]

I got myself
The Complete Reference JavaServer Faces
which seems to cover all interesting bits.

Note: I have only been looking at JSF for 3 weeks.

[Tom Fulton]

They are both good books, and I second The Complete Reference: JavaServer Faces recommendation. The bad news: none of them are sufficient on their own. Even with all 3, some features a just poorly documented (see my post today "JSF notes on Events" for an example).