Things haven't changed much since KDE 0.9x, apparently.
For a project I did back then, we created a dummy account, configured it ,
stored the .kde tree and Desktop files in /etc/skel, then used a script to
cpio the tree into the user's home dir, and used chmod -R to give her
ownership.  The following article I found gives a detailed account:

http://articles.linuxguru.net/view/138


>
>We're setting up some Linux workstations in our labs, and I'm trying to 
>figure out how to customize the KDE environment for all who log in.  But 
>not having any luck.  Does anyone know where global config files are 
>stored for KDE?  Are there global config for KDE?  We're using RH 7.3.
>
>Thanks...