In Oct 2002, I have a 2 hour seminar on Webmin to the St. Louis UNIX Users Group.
The seminar was a couple of hours long, and showed the entire group on webmin.
Included: Basic use, Webmin Capabilities, Integration Capabilities and examples, and lots more..
Here's an old link about it..
http://www.sluug.org/cronicle/2002/2002-10.html