Not sure what you mean by a TCP/UDP server, but I'm assuming you mean things like HTTP, FTP, etc. A great place to start is at the Linux Documentation Project
www.tldp.org . There are plenty of HOWTO's for setting up just about any kind of server you can think of. Also the software developers themselves often have more specific directions (for example,
www.apache.org has a good howto on how to get the apache webserver up and running).
HTH
