Is there a single list of the various "stock" configuration files and 
directories used by the various applications that come with EL?  For 
example, printing configuration is in /etc/cups/*, and there are many 
other examples.

At one time, this was not as needed as today -- there were far fewer 
applications, and most (all?) had configuration files that were in /etc 
.  Many (most?) of such configuration files in the current epoch seem to 
be in some path from /etc, but it can be a bit of a hunt to find these 
files.

Yasha Karant