It normally isn't possible. When chatting you have a connection with the other computer only through the host site (Yahoo). Only they will have the IP address and they will not tell you. Even if you obtained the IP you could do next to nothing with it. You cannot trace it back to obtain personal information such as a physical address about the chat partner. You must also understand that your chat partner may not be using their own Internet connection. In such a case tracing is virtually impossible.
The information on Computing.Net is the opinions of its users. Such
opinions may not be accurate and they are to be used at your own risk.
Computing.Net cannot verify the validity of the statements made on this
site. Computing.Net and Compnet Ventures, LLC hereby disclaim all responsibility
and liability for the content of Computing.Net and its accuracy.