Dawson, Julian. 2011. And On Piano ... Nicky Hopkins: The Extraordinary Life of Rock's Greatest Session Man. Foreword by Klaus Voormann. San Francisco: Backstage Press.
Here's a link to what I think is the publisher. Different press name, but I think they're under the same imprint somehow.
Anyway, I know a little bit about this project and anticipate that this is going to be an excellent book, a really important addition.