The System Administrator's Guide for Red Hat Enterprise covers kickstart. All of the Red Hat docs are a free download, and are worth grabbing.
Personally I wouldn't use NFS for kickstart installs. As a rule you shouldn't enable NFS unless you absolutely need to, and kickstart doesn't use any of the features that make NFS sometimes necessary. I exclusively use HTTP (Apache) for installation and updates (with yum), and restrict access to the relevent shared directories by subnet or domain.