"Go for Beginners" by Iwamoto is a classic [1].

"Go: A Complete Introduction to the Game" by Chikun Cho generally gets very high recommendations [2].

When you finish your first book a good followup is "The Second Book of Go" by Bozulich [3].

Finally, the series "Graded Go Problems for Beginners" is excellent [4]. Volume I problems are suitable for beginners starting as soon as you learn the rules.

If you have an iOS device, take a look at smartgo books [5]. Chikun Cho's book listed above and the graded go problem series are available from them, as are many many other books. These books are in an interactive format that works with their free reader app.

[1] http://www.amazon.com/Go-Beginners-Kaoru-Iwamoto/dp/03947333...

[2] http://www.amazon.com/Go-Complete-Introduction-Beginner-Elem...

[3] http://www.amazon.com/Second-Book-Beginner-Elementary-Books/...

[4] http://senseis.xmp.net/?GradedGoProblemsForBeginners

[5] http://gobooks.com

I liked An Introduction to Go (http://www.barnesandnoble.com/w/an-introduction-to-go-james-...) and The Second Book of Go (http://www.amazon.com/Second-Book-Beginner-Elementary-Books/...)