LinuxQuestions.org - Looking for better documentation for Nagios

In Nagios (a network monitoring system) some basic things like figuring out where various config files are to be placed (e.g. the file names) seems to be just outright missing in the documentation. And many links to documents just go to pages that link to somewhere else, sometimes over and over, and just end up at a dead end, with the subject never being documented, such as NRPE.

I originally started at the links in the Nagios web page, and found very little. I was give a URL of "http://nagios.sourceforge.net/docs/3_0/toc.html" which has more links. There is data in a lot of these links, but it's incomplete ... typically showing what to write, but not describing where it goes.

Anyone know if there is any better documentation somewhere, even if just a starting document? And please do not give me an install document. It's already installed. I don't yet need another "quickstart" document that just tells me how to do what I do not need to do (I'm trying to avoid getting useless "help" by stating this).

A document that would describe EVERYTHING to do on an existing Nagios system, to add ONE EXAMPLE service to monitor ... what file to add or modify ... what to put in it ... just to monitor that one specific thing, would be nice. But this needs to be something better than the incomplete examples that don't give all the points.

Please, no videos ... text documentation is what is needed. Graphical illustrations in that text is OK.