En Backploit han publicado manual muy bueno creado por juh En el que explica muy claramente como usar Nmap desde 0.
Indice:
[+] Title: Advanced And Comprehensive Use Of Nmap
[+] Author: Juh…
[+] Contact: juhscr@hotmail.es
[+] Date: December 2010
[+] Software Link: http://nmap.org
[+] Tested On: Windows, Linux, Unix, Server’s, Solaris
[+] A little paper about types of scan with nmap tool :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
-0v01- Introduction
-0v02- Little Example
-0v03- Types of scan
-0v04- Options 4 scan
-0v05- Creating and testing our type of scan (legal)
-0v06- Conclusion