David Grinspoon
Read his latest book "Lonely Planets". In this Grinspoon gives an insightful history of the SETI debate through personal observations of Drake and Carl Sagan. He notes that the Drake Equation was jotted down at what was probably the world's first SETI conference.
His book is interesting, and although section 3 seems to be wandering in the wilderness, it does finally arrive somewhere useful. I disagree with some of what he says there but most of it is interesting and useful.