Visit any of the twelveteen bazillion free email web pages, such as Hotmail, or Yahoo, and get a free secondary e-mail account. Then use that account as your return e-mail for when you do public posts to newsgroups and message boards. Most newsreaders usually let you enter what e-mail shows as your return address. First, don’t enter your main e-mail address here, but your secondary e-mail. Second, add the phrase no-spam somewhere in the e-mail address. That way, every person who wants to send you a serious reply, knows to remove the no-spam part. But any spammer that automatically harvests e-mail addresses will get a bad address.
Don’t give out your main e-mail address freely. Think about who you give it to. Use it only for personal e-mail to work or friends, don’t use it in forms that you fill out (paper or online). Use the secondary account instead.
Most decent e-mail programs have spam filter ability already built in. For example, the new version of Outlook Express has a cool spam filtering system that will check every mail you get and if it looks like junk, put it directly into the trash.
See if your e-mail reader supports rules. sometimes you can use rules to say “any e-mail that comes in and does not have my actual e-mail in the to or cc field, trash it”. You might have noticed that spam never actually has your e-mail in the header, just some list name or other weird stuff.
If you get spam and it is from a serious outfit, they will usually at the bottom of the e-mail give you the option “if you don’t want to get e-mail from us, reply with the word remove in the subject line” or something like this. In this case, do it. But if you get spam that does not have that option and seems to be from some scummy source, don’t reply to them and ask to be removed. Instead, they’ll know they found a valid address and keep sending you more spam and sell your address to many more places.