Mark Ribowsky, Signed, Sealed, Delivered: The Soulful Journey of Stevie Wonder (2010)
This is a relatively thorough and easy-to-read biography.
Steve Lodder, Stevie Wonder: A Musical Guide to the Classic Albums (2005)
For the fan, a close look at Wonder's musical legacy. This book is one writer's personal take on the music and performance elements of many of his classic songs.
Craig Werner, Higher Ground: Stevie Wonder, Aretha Franklin, Curtis Mayfield, and the Rise and Fall of American Soul (2004)
This is a slightly more academic book that discusses the rise of soul music in terms of its social and political significance.
Dennis Love and Stacy Brown, Blind Faith: The Miraculous Journey of Lula Hardaway, Stevie Wonder's Mother (2002)
This is the authorized biography of Stevie Wonder's mom.