Newbie/Neophyte

Hello,

I'm new to this list and RPM management.  Can anyone point me to some 
"good" documentation on how distributions such as Fedora and/or RedHat 
are created/packaged starting from just a collection of RPMs and nothing 
else.  I've done lengthy searches on the Internet and have only found 
info that appears either outdated or not applicable to my needs.  In 
other words, doesn't get into enough details.  I'm here because I know I 
have to do something with a comps file and probably use createrepo() at 
some point, which lead me to this list.

I understand there are various tools such as "revisor" (which I am 
looking at now), but I need to understand how packages are put together, 
not just rely on a tool to do it for me.

1) What is .discinfo and where can I find a description of each 
key/value pair
2) What is .treeinfo and where can I find a description of entries in 
it, as well as a description of how it functions.
3) If I want to build something with multiple DVD's, how does anaconda 
know when to call for "the other disk media"?
4) Lot of talk on Internet about comps.xml, but in RHEL I see 
comps-rhel5-server-core.xml  and there is no comps.xml shipped.

If the ONLY thing I have is a directory of RPMs, what's next?

If this is the wrong list to ask such questions, I would appreciate a 
pointer to the proper forum.
Thanks in advance for any help you can provide.
Jon