Protect Your E-Mail Address
Don't give it to someone you don't know, encode or hide it in your web pages and have one or more spare e-mails addresses for lists and groups.
Keep Your Virus Protection Up To Date
Threats are getting more sophisticated and you don't want to be the person who gives the spammers an address book full of valid e-mail addresses.
Never Reply to Spam
Replying to spam is often the worst thing you can do. If it annoys you then report it and that means by post to the appropriate ISP, authority or embassy. Just think what 10,000 letters a week would do for efficiency.
Use a Desktop Filter such as POPFile
This categorises all e-mails that are received by your computer. Use it to sort spam from wanted e-mails and to separate the latter into your required folders.
If Problems Persist Use a Mail Server Filter such as SpamStomp
I have to admit that I don't like mail server solutions, as there is always the chance that an important e-mail will not get through. I would always use something like POPFile first.
But if problems persist, especially as in the problems with freedomfarm.com, then you should think about imposing a mail server filter such as SpamStomp.
If you do use a mail server filter, then make sure that you get reports of all the e-mails that are not delivered.
Identify Yourself with a Signature
Always put a decent signature on an e-mail, as this is not only courteous, but it enables any spam filters to recognise you as friendly. I always put a decent quote into the signature, but in most cases company details, any disclaimer and policy are all that is needed.