If you're just looking to simply add a user, using the command do the following as root:
This will add the user "phpguy". This can be changed to whatever you want the username to be. To set the password for "phpguy"
This will prompt you for a new password for "phpguy" and ask you to confirm it.
Hope this helps.
P.S> That RH9 Linux Bible is an excellent book. I paid $80 for it and have never regretted it, and it is a wonderful buy.