Most of the examples I have seen have been in C as opposed to a true OOP design (as in C++). Most C++ code relies on C linkage and uses stuff in sys/socket.h and files like that.
For example, Addison Wesley publishes "Effective TCP/IP Programming" which is C, and the Stevens books are also C.
I'd say that a book on TCP/IP programming for C++ that uses STL containers/algorithms and does stuff like read from sockets with overloaded operators, etc., would be very cool.
I don't think there is anything standard but you might even find some open source libraries that aren't "just C".