In October of 2006, Leonard Rosenthol (the owner and Chief Technology Officer of PDF Sages), was hired by Adobe Systems
as a PDF Standards Architect focusing on the development and
promotion of international standards for PDF. At that same time, PDF
Sages stopped conducting business.
If you are looking for the software products developed by PDF Sages, they continue to be sold and supported by Apago. Contact them for PDF Enhancer, PDF Appraiser, PDF Constructor and others.
If you are in need of custom software development, I recommend the following companies.
If you are in need of PDF consulting services, I recommend Thom Parker of WindJack Solutions who subcontracted with PDF Sages on a number of projects.
If you want to continue reading Leonard's "Wisdom of the Sage", read the blog.