What is running on your board exactly? When it is an Linux/Ubuntu, there is nothing special, you can use any TCP/IP/sockets documentation for Linux that is out there.
When you are using StarterWare bare metal code, you will find it makes use of lwIP. There is a extensive documentation available from this project and StarterWare comes with some examples about how to use it. In this special case it is not programming with a standard socket-API but access to RAW lwIP functions.