This is what Gary wrote to me:
Gary Corbett wrote:The book provides an in-depth look at the cycle tour industry and details how to plan, book and ultimately get the most out of an organised cycling holiday. I believe the information contained within the book makes the process of planning, booking and enjoying a guided or self-guided tour all that much easier and clearer and that the information will help you to ultimately increase your tour bookings
I havn't read the book though can imagine that it is useful and pretty affordable if you are new to cycle tours.
Feel free to comment or suggest other useful resources.