The Shellcoder's Handbook
Chris Anley & John Heasman & Felix Lindner & Gerardo Richarte
Linux in a Nutshell
Arnold Robbins & Ellen Siever & Stephen Figgins & Robert Love
Using and Administering Linux: Volume 1
David Both
White Space Is Not Your Enemy
Rebecca Hagen & Kim Golombisky
CompTIA Linux+ Guide to Linux Certification
Jason Eckert