According to mujitra, this is “the bible for Japanese newton owner.” Flipping through the book, you can understand why. Published by NTT in 1997, Newton Spirits is an illustrated how to guide, product history, technology platform reference, and overview of all things Newton — including software, hardware, screenshots, prototypes, and specifically the use of the Newton in Japan.
Japan’s Amazon.com has it available, though you have to wade through the Japenese to order your own.
Morgan at Makkintosshu grabbed his own copy recently. So jealous.