I often get asked this so I thought I'd make a list to redirect people to:
List of panels that can be used on a Slice:
Most basic
Free
In no particular order..
Not Free
Cutting Edge/Crazy and Free
I just heard of zervex too.
The sound effects on their front page scared me.
I'd like to add on the list: ehcp.net .. seems very comprehensive .. works best with the latest Ubuntu. Installs a LAMP stack for you with options for installing things like wordpress.
Installation Instructions .. tut and vid.
I'd probably go through the slice setup article first to lock things down.