On the Site Map page look for "Find Contact Information" under the CONNECT category - Click on it.
Enter the ID of the buyer or seller and the transaction ID.
It will request the information and send it to you via email.
Link might work: http://www.ebay.com/sch/ebayadvsearch?_skipfnorm=1&_sofindtype=9
0TcBNRKIQSs6Q~~_7.JPG "http://i.ebayimg.com/04/!!f4kBCg!3U~$(KGrHqR,!loEz+5f)0TcBNRKIQSs6Q~~_7.JPG")
)