It appears the only place to get Harley's latest book is through the Federation of Flyfishers and is titled as follows:

His recently published book, offered as compact disk by the Federation of Fly Fishers Hunt?Don?t Pray?for Fish: Techniques and Strategies for Fly Fishing from a Drift Boat is a culmination of almost 60 years of guiding and fly-fishing experience gained from fishing all over the United States and parts of Canada and Mexico.

If you're interested here is the FFF link: