almost forgot you asked for a ip tracer well here is a link to one online dont know what your going to do with it but here it is
http://www.dshield.org/ipinfo.php
if you really wanna know how easy it is to find an ip on yahoo mail click the link that says show all headers and youll see just how much info is contained it just an email header so getting an ip is really easy Also mostly worthless if you have a good antivirus and you are email savy ( not opening or downloading anything that come as an attachment without scanning it first .BTW Microsoft does'nt send out emails about updates If you get something with an attachment and you dont know the sender delete it Also never aceppt a file transfer form some one you dont know in chat it could have a virus or a trogan in it. someone wants to show you a pic or a file have them email it to you so you can scan it for any nasties that might be inculuded .