As always I would suggest everyone use good anti-virus software on any computer that is conected to the internet.
Keep virus definition files updated, and enable email scanning.
You can also scan free, from the 'net, using professional scanning software, constantly updated, at: http://housecall.antivirus.com
It downloads and installs an activex control, so if you're running spybot or somthing, you may need to change a setting to let this install.
You can check out the senders IP by looking at the header information in the post. In the example you give, the I.P in question is 18.104.22.168 ( the email 'name' is alterable from the senders end, so does not necessarily show the 'true' sender.
using a site such as http://centralops.net/co/
select Domain Dossier and enter the numbers ( I.P. ) into the domain or IP address
box and click "GO" the information provided gives you information abotu the sender.THEY MAY NOT BE AWARE THEY ARE SENDING EMAILS IF THEY HAVE AN INFECTION ON THEIR MACHINE
..So instead of sending off a nasty email to them or their service providers, a polite email is always a better option.
Please check out the security section of the forums regulary as 'updates' and warnings are regularly posted in their.