Most of the writings and books by Dharampalji can be hard  from the following sources:

 

1. Other India Bookstore Goa (Claude Alvares)

http://www.dharampal.net/

2. SIDH, Mussoorie (Pawan Gupta) 

http://sidhsri.com/

3.Dharampal Shodh Peeth, Bhopal

http://www.dharampalshodhpeeth.in/literature.php?by=d

4. Centre for Policy Studies, Chennai/Delhi

https://www.cpsindia.org/

 

Much of the materials are available as PDF free downloads from these sources who also sell bound volumes suited for libraries etc.