I finished a biography of Stevie Wonder yesterday, "Signed, Sealed and Delivered: The Soulful Journey of Stevie Wonder" by Mark Ribowsky. It was not a good book. He seems to have spoken to perhaps three people who know or knew Wonder; most of his info about Wonder's life is from magazine articles and interviews. He does an OK job discussing the music, but even there, analysis is given short shrift. The one interesting story he digs up has to do with how Wonder used and discarded Malcolm Cecil and Robert Margouleff, synthesizer whiz kids and the producers of most of his greatest albums (including Talking Book and Innervisions).
I wish books like this were honestly marketed, as being not really biography--you come away from this with no real sense of what Wonder the person is like--but music journalism. Had the author focused more narrowly on the music, I might recommend this, but I can't. However, the book has sent me back to the music; I popped Innvervisions in my car CD player today, and I've got Talking Book and Songs in the Key of Life ready for the next few days.