There was an interview with the author of this book in the English Mail on Sunday at the beginning of May.  In it he did talk quite a bit about how his dog had been rehomed once he finished his racing career.

On the front cover of the MoS magazine was a picture of a beautiful black and white dog (not the dog featured in the book).  I thought he was my Freddy's double.  When I checked this dogs details on greyhound-data.com I found out that he is Freddy's nephew!! No wonder they looked so alike!!