Blowing Zen books:
Blowing Zen Honkyoku
Blowing Zen: Expanded Edition
Blowing Zen and Blowing Zen II
Note: The Expended Edition include the content of both Blowing Zen and Blowing Zen II. All books comes without companion CD.
Companion CD:
@ Shakuhachi.com (book too)
@Gumroad
Shakuhachi Flutes:
@ Shakuhachi.com