Linux sites
 
Linux.org
Root.cz
ABC Linuxu.cz
Freshmeat.net
 
Gentoo Related
 
Gentoo.org
Gentoo x86 Handbook
 
Slackware Related
 
Slackware.com
 
Linux How-To
 
Gentoo Basics
Slackware Basics
*buntu Basics
Linux Commands
Linux Configuration Files
Kernel Compilation Guide
Example of Linux Firewall