There is a hidden file NAME.zip for each directory NAME. This file contains the compressed (zipped) content of this directory. You can retrieve it as:
http://www.ccl.net/cca/software/SOURCES/C/NAME.zip
For example, for directory PDB++, enter the URL
http://www.ccl.net/cca/software/SOURCES/Cpp/PDB++.zip
into your browser to retrieve it to your local computer.