I have read the book from Lincoln D.Stein and it is fine as an introduction to network programming in Perl. If you know nothing about the matter you will learn a lot reading it.
Reading W. Richard Stevens book as recommended by repellent may also be a good idea because Perl network built-ins are just light wrappers around the C APIs provided by your OS and it is very useful to understand what's going on under the hood.
In any case, your concerns are founded. None of those will teach you modern Perl network programming techniques, as for instance how to use frameworks like POE or AnyEvent. But once you know the basics, getting to learn those should be pretty smooth.
Actually what I would really advise against doing is trying to learn how to use some high level framework without understanding the network programming basis.