Will Wright is very fond about reading. It gave him the inspiration for many of the games he made. Like Urban Dynamics by Jay Forrester was the book he read before making Sim City. the Gaia theory from James Lovelock (SimEarth), A Pattern Language by Christopher Alexander (The Sims), and many, many others.
At the 2008 GDC, he was asked about the most recent book that had captivated him. He replied with "The Ghost Map: The Story of London's Most Terrifying Epidemic - and How It Changed Science, Cities and the Modern World." by Steven Johnson.

What not many people know is that Wright is starring in several books himself and also that he's in the process of writing a book himself. Wright: "I'm about halfway through the organization of it. The book is on design; it is a general design book. It's going to be a very graphic book". He made this quote on May 11, 2006. There is no info what so ever about this book but it's highly possible that his busy work on the Spore game prevents him from working much on it. Now Spore is finished, we may hear more about it soon.

Another book with his name on the cover is "Mirror Lake -Images of the Fripp Island Habitat". Mirror Lake is a place where the Wright family, Joell Jones, Will Wright and Cassidy Wright, occasionally go to on vacation.
The introduction tells us that Wright visited Fripp Island since he was a young boy and stayed with his family in a rustic hotel. Will introduced Joell to the island in 1981, where she started sketching its environment and wildlife. Cassidy has been visiting the island since her birth in 1986. By the year 2000, Cassidy and Will begun photographing the island. As more people discovered the beauty of Fripp, the landscape was drastically altered by hotels, restaurants and golf courses. With this book the Wright family offered the images in the book as a better awareness for the area.
The book is edited, introduced and designed by Jan Kamp (jcampstudio.com).

"SMARTBOMB: The Quest for Art, Entertainment, and Big Bucks in the Videogame Revolution" by Heather Chaplin and her husband Aaron Ruby. The book features intimate and individual portraits of many of the biggest names in video games, including CliffyB - Lead designer of Epic Games and co-creator of Unreal, John Romero - Creator of Doom, Shigeru Miyamoto - Game designer for Nintendo (Super Mario, Zelda,etc), and many others.
The chapter on Will Wright is an interesting read; the autor follows Will Wright on a typical day and shows the Spore game he's working on. There's also a large piece on Wright's personal life and his history.

Wright also wrote a few forewords:
- Will Wright has a lenghty foreword in "Theory of Fun" which you can read here: theoryoffun.com
- A foreword in the book "Persuasive Games".
- A foreword in the book "Creating Emotion in Games: The Art and Craft of Emotioneering"