DEFPOTEC
One thing that you can check is in a text version of the total email message that will give you the path that the message was sent through. In Outlook Express it is gained by :-
Selecting Email Message
Select :- File
Properties
Detail (TAB at top)
This gives you a text version of the total email and you can then view it in Notepad by selecting the "Message Source" button. The top section of the file shows the path taken by the email and the senders details. It can then be possible to back track by contacting the organisations/companies that the email came through, a lot of effort and they probabily would not help to much.
There are still sites on the web that allow for anonymous emails, where the sender is hidden by a third party and it is impossible to determine the sender (these are used a lot for sending info to the newsgroups !!!!). Not much use I know.
The other thing to do it to automatically delete the emails when they are received (possible in Outlook Express) so that they do not cause any problems.
Always have a better day than yesterday