Besides G-Talk there are several other IM messengers that are being used worldwide but the main ones are MSN and AIM. If we deeply analyze the connection between you and your IM friend, we come to know that your computer is not connected to your friend’s computer. In fact, you both are connected through G-Talk's server, which then transfers your messages to the friend and vice versa. The image shown above will clearly explain this connection.
The IM service used by the two parties is connected with a server, so if you intend to find out the IP address, you can only track down G-Talk’s IP address instead of that with whom you are IM’ing.
TCPView is a software that helps in finding out the detail listing of TCP along with UDP's endpoints. When the TCPView initializes its process, it will list down all IP addresses along with the domain name and the versions.
After the usage of TCPView query and response protocol, WHOIS is used to help you in knowing the domain name along with the IP address of the anonymous system.
After using that, you will find 126.96.36.199 IP address which is owned by Google for G-Talk.