The first volumes paints its ideas with a broad brush. It is meant to illustrate ideas without trying to solve every problem keeping humans off Mars. Volumes II and III (due out in a few years), respectively, explains why we should go to Mars, and provides many specifics of the technical, economic, and political structures proposed.
The book is available on most on-line booksellers, including Amazon.com, Barnes&Noble.com, and through the publisher at iUniverse.com.