Some people don't know their IP Address. Well, if they use dynamic IP, such as dial up communication, that's normal. But if they use a dedicated IP for their servers, it's best to know your own IP Address. There are several ways to do this, but one of the most easiest one is by going to some site and have them told you. I found this URL is working just fine, but only a simple statistic is revealed. If you want to have more detailed information, try to go to this URL. Your IP address will be revealed by a girl's voice (Be careful, her sound is quite loud, so you might want to lower your volume level).
PS: Don't try this on public speaker!!