LAN question

Hi, how could I search (TCP) in a network (LAN) for a server? do I have to check all IP's in my Class C Net ? 1 - 254 ? expect my own. how does games like warcraft 3 quake aso. do this? EDIT: and what is, if my LAN contains more than 1 Class C Net's how to do that ? thank you Dominik [edited by - Dominik_78 on January 1, 2003 3:26:25 PM]