The book was written by one of the two participants, Rinker Buck, who is currently a staff writer for the Hartford Courant. A few years ago he won an award from AOPA for his aviation writing, in particular a series of articles dealing with the JFK crash. (Part 1, Part 2, Part 3, Part 4, Part 5.)
Rinker wasn't a licensed pilot at the time, as he was too young. So most of the actual flying was done by his older brother, Kernahan. To this day, Kern Buck is an active CFI.
A random internet search today turned up this video -- obviously from a home movie camera -- of Kern Buck's first solo in 1964. According to the book, Kern actually soloed four different airplanes that day. Quite a feat for any budding aviator. If you enjoy the book as much as I do (the abridged CD, read by Rinker himself, is even more fantastic), then perhaps you'll enjoy this video as well!