Your spam can be handled a few different ways! Contact WGC Designs to have us turn on a basic server side filtering. Server side filtering will block only blatently spam messages and anything in question will be not be blocked and will include "Possible Spam" in the message title.
Other options include:
POSTINI, Now google Apps is always a nice option that will block a majority of your spam messages seamlessly at a very limited monthly fee. They do not have much for technical support services with it so if thats an issue I would use a 3rd party spam filter.
Standard is a free tool for Outlook, Outlook Express and Windows Mail that automatically and efficiently filters spam and
Also see Wiki Spamming Information on all things Spam.