The Lost Art of Handbalancing website is reselling an old classic book:
The True Art and Science of Hand Balancing written by two men, Professor Paulinetti and Bob Jones.
They’ve repackaged the original content in a modern format. Sounds expensive to me at $49. (Check the comments below for feedback from those who purchased it.)
Certainly hand balancers today are better than ever before. The art not at all “lost”.
Acrobatic gymnasts do the best stationary handstands. Break dancers the best dynamic handstand work.
Still, acrobatic historians may be interested in this product:
The True Art and Science of Hand Balancing
Gymnastics Coaching.com 