This is a pet peeve of mine. Your instructions are for how to get a free domain name, not an IP! I don't know why so many people here keep calling domain names IPs. They are NOT interchangeable terms.
Yeah, it is different terminology, however I think the mix-up originates from web forms or people asking "What's the IP of the server" and someone responding with "somedomain.net", and so begins years of terminology confusion.