I read that he had just released his biography, and am now contemplating buying it.
Years ago, Levon Helm, the drummer for the Band, published his autobiography "This Wheel's on Fire". I read it when it first came out, and thoroughly enjoyed it. I will probably buy this book as well, to hear Robertson's side of the story. The Helm book had a lot to say that was not favorable to Robertson.
Regardless, I was inspired to play some Band music from Youtube, and came across footage of Van Morrison doing "Caravan", from the concert "The Last Waltz". It's really amazing, and I recommend it.