Disturbing e-mails from Hotmail…..

Somebody from our office is sending highly offensive and disturbing e-mails through Hotmail. Is there a way of finding out where the Hotmail account is coming from as we are trying to find out who is doing this?? I know that the Hotmail server sits on the West Coast of the US but I need to know whether it can find where it originated from in Australia, Melbourne as this is where we are situated.

Look forward to a response.

Mil