The main web site for SELinux is provided by the NSA:
The NSA's SELinux
The web site includes a FAQ, available at http://www.nsa.gov/selinux/info/faq.cfm.
In addition, various Linux distributors and interested parties provide SELinux-related web pages and FTP sites. Among the most popular and useful are:
Kerry Thompson's SELinux
http://www.crypt.gen.nz/selinux
Network Associates SELinux
http://opensource.nailabs.com/selinux
Russell Coker's SELinux
http://www.coker.com.au/selinux
SELinux for Debian
http://www.microcomaustralia.com.au/debian
SELinux for Distributions
http://selinux.sourceforge.net
SELinux for Fedora Core
http://fedora.redhat.com/projects/selinux
SELinux for Gentoo Linux
http://www.gentoo.org/proj/en/hardened
SELinux for Red Hat Enterprise Linux
http://leapster.org/linux/selinux/suse
SELinux Wiki (German and English)
http://www.securityenhancedlinux.de
Sourceforge SELinux
http://sourceforge.net/projects/selinux
Tresys Technology SELinux
Several mailing lists address issues related to SELinux. Among these are:
The NSA's SELinux mailing list
http://www.nsa.gov/selinux/info/list.cfm?MenuID=41.1.1.9
The Red Hat Fedora SELinux mailing list
http://www.redhat.com/mailman/listinfo/fedora-selinux-list
The Gentoo Hardened mailing list
http://www.gentoo.org/proj/en/hardened
You can use these lists to learn more about SELinux, get help in installing and using SELinux, and participate in the development of SELinux and related products.