I know. But you will get the right address on a computer with a direct Internet connection. But if you are on a network that shares an Internet connection all you will get is your NIC's private IP address (192.168.xx.xx for example). However if you have admin access to your gateway or router you will be able to see your WAN IP address which should be your actual external (red zone) IP. But, I was only listing another way to get your IP. In this case
http://www.whatismyip.com/ would be MUCH easier as LOTR suggested. Good luck.
deepblue