Greil Marcus, When That Rough God Goes Riding: Listening to Van Morrison (2010)
There are literally dozens of books about Van Morrison. The newest, and possibly the best, is by cultural critic and Rolling Stone regular, Greil Marcus.
Clinton Heylin, Can You Feel the Silence?: Van Morrison: A New Biography (2004)
This is for the hardcore fan, the reader who won't be content with an abbreviated look at the Irish artist's life. Almost 600 pages long, the tome follows Morrison from his working-class roots through "the dark end of the street" at the turn of the century.