If we can trace the IP from a user of Skype, and while we are already in conversation enough to do the following:
1) Open the Task Manager of Windows (Ctrl + Alt + Del)
2) choose View-> Select Columns-> and check the option PID
3) Find the PID of the application of Skype
4) Open command prompt (Start-> Run-> CMD)
and press Enter
We will see that this command will display all our connections and having the PID of Skype (step 3) we can find the IP address of the user looking to talk to the external column addresses.
Note: Because the Skype conversation is through 3rd party server we show the connections and the server of skype that we are connected so to not confuse the IP's are better to send a file to another user or to speak for some time (more than 1 minute ) to remain stable on IP connections.