I am a little old school and would love to buy some physical books to help me learn Houdini. I cant seem to find any. So what books do you recommend to help in the process of learning. I am also open to any math or programming books.

Hey icyou2020,

to my knowledge there are no recent books covering Houdini. However if you are into classics from 2006/2007, there is:

• The magic of Houdini, by Will. Cunningham, Peter Bowmar, Jason Iversen, Dave Johnson
  
• Houdini on the Spot: Power User Tips and Techniques, by Craig Zerouni
  

The closest you can get to a book would be the official online documentation and Matt Estella's CGwiki.