see topic How to find my own ip-adress?
. You probably want to play on your own server as well. Assuming you are playing on the same computer as the server is running on, all you have to do is start another instance of Quake3, and connect to your server the same way as your friends do who play over the internet, except that you should enter \connect localhost instead of the ip-address.
You can get your ip address by clicking this IP-Details.com . It also provides the domain host search, ip search, internet speed test tool etc.,
