You can go to these pages to check your IP address: http://www.simflex.com/ip.htm and http://www.ipaddressworld.com. You need to know the host computer's IP address to connect to his computer in order to play multiplayer games. If you use dial up services use as AOL or Prodigy, your IP address will be different every time; your IP will be the same if you have cable modem, T1, or some DSL connections.
What is ICQ?
ICQ, or "I Seek You", is a free instant messenger program that lets you chat with your friends and family members easily. You can download ICQ here. You will be assigned a unique ICQ number when you register. ICQ alerts you when other players (on your contact list) are online. You can use it to send instant messages to multiple recipients and setting up a multiplayer game is much easier this way than by email. If you don't have ICQ, I strongly recommend you to get one. It's one of the world's most popular program.