Mastering the Art of Fabric Printing and Design
Mastering the Art of Fabric Printing and Design by Laurie Wisbrun is is a book I am always happy to recommend to people who are interested in learning about how to do pattern design.
It was published in 2011 by Chronicle Books, and includes heaps of great tutorials and technical advice, as well as great interviews with a host of professionals in the industry (myself included!).
Get yourself a copy!