Network administration with FreeBSD 7 covers not only network administration itself but starts with a general introduction in topics like system setup, configuration, RAID, package management and jails. It continues to cover practically all aspects of network administration, from setting up basic IP (IPv4 and IPv6) to firewalls, tunneling and network servers (SSH, DNS, Apache, etc.).
The book is full of examples and dives little into theory or background of the subject. This can be either good or bad, depending on your viewpoint. In any case, it gives enough information to point the user in the right direction in case he wants to go digging. This is not the kind of book that's extremely comprehensive about a topic but it gives to-the-point advice on common tasks, which is what most administrators just starting with FreeBSD really need.
I'm puzzled by the title - not that there's no network administration in Network administration with FreeBSD 7 but the networking part is roughly 1/2 of the book, the rest being about generic systems administration of FreeBSD machines. Maybe it could have attracted more readers with a more accurate title.
There isn't much that can be faulted in the book. The language is at times awkward (maybe it should have been read and edited more carefully by a native english speaker?) but there's nothing serious that affects understanding of the topic. I'd also like references to man pages and a bit more on how to find documentation on the topics external to the book, but that's it for complaints.
I'd say the book is targeted to users beginning with FreeBSD but at least some experience (even if it's only cursory) with Unix or Linux systems administration (e.g. it's assumed that you know that you want to set up IP addresses on the network interfaces). For this audience, it gets full marks.