Here is a list of other Linux sites that you might find useful.

Linux Documentation Project
Huge quantities of Linux documentation, including HOWTOs, man pages, FAQ’s, etc.

Linux.com
Linux information, software, documentation, how-tos, and answers

JustLinux
Linux Help Forums

LinuxForums
More Linux Forums

SourceForge
Search site for open source software

RPMFind
Search site for Red Hat Package Manager compatible software packages

Linux Today
Linux and open source news

Using Access Control Lists on Linux
A tutorial showing how to enable Linux Access Control Lists and some basic ACL permissions