Depends what kind of server you're writing. If you want to handle the networking with your server, you can use the example in the IO::Socket manpage:

$sock = IO::Socket::INET->new(Listen    => 5,
                              LocalAddr => 'localhost',
                              LocalPort => 9000,
                              Proto     => 'tcp');
[download]

and then read from $sock.

If you are on *ix, you can have the OS handle the networking for you by using inetd.

I don't know of any generic 'server' tutorials, but if you are stuck at a particular point that could make a better question.