The Blowing Zen recordings are available from Kunaki , Gumroad , and BlowingZen.org.
The Shakuhachi is an ancient flute that captivates many who cross its path. Hidden in its simplicity is profound possibility. The windy, resonant sound of the Shakuhachi brings deep serenity to sympathetic ears. For the devoted player, it is also a spiritual tool for training the mind and breath. Most notably, Zen monks have using the Shakuhachi for centuries to train mind and breath through the practice of Sui Zen (blowing Zen) using Buddhist music composed specifically for the Shakuhachi. “Blowing Zen” guides you step-by-step from producing sound to playing Buddhist Meditation music. Also included are detailed build-your-own shakuhachi instructions. The Blowing Zen Companion CD (available separately) contains the Japanese folk tunes, chamber music and Buddhist composition “Hi Fu Mi” taught in the book. It also includes examples of timing and standard Buddhist music phrases. Visit BlowingZen.com for FREE audio and video recordings of the material covered in the book.
Lots of good information, both basic and advanced techniques explained and illustrated. Also included are sections on making a basic PVC flute and detailed instructions for harvesting bamboo and crafting a traditional shakuhachi.
I highly recommend going to https://gumroad.com and purchasing the sound files for more than an hour of musical examples and performances of the pieces notated in the book.