Index -> Interface -> Preferences -> Account Info

Account Info

This page of the Preferences screen lets you determine what other players see when they click on your name in a User List and Get Info on you. You can write a personal message, include details like an ICQ or AIM handle, and decide which elements of your information are viewable to everyone, no one, or just your buddies. You can also select your Avatar, the graphic that will appear next to your name in all lobbies and games.