Learning Linux System Administration

• The Linux System Administrator's Guide
  
• Linux System Administration Tools
  
• Linux Administration Made Easy
  
• UNIX Tutorial: Absolute Beginner to Linux "Expert" in 10 Lessons
  
• Linux Network Administrator's Guide, 2nd Edition
  
• Linux Newbie Guide by Stan, Peter and Marie Klimas
  

Ok so I'm lazy and don't really have anything to say about these sites yet. Look here for that.