search around your email program and see if there are any options to block certain addresses. if not, open the email (after scanning it for viruses/making sure its ok) and see if theres somehting in it that says "stop sending me blah blah" or "do not email me newsletters" or anything like that written in the actual email itself. theyre usually links, which lead to where you can cancel something.
if nothing works, make a new email address. you can use your aim screename @aim.com, like "example@aim.com" would be your email if example was your sn. you can also use hotmail, yahoo, or search around the web for free email providers.
and finally, if you don't feel like making a new email, search google for "stop emails" or "block emails", you can probably find out there too :)
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