Often, when you enter a sweepstakes sponsored by a magazine, there is an implied subscription UNLESS you click a button that says you already subscribe or DO NOT WANT to subscribe. Even if you click that button, on the resulting page you may find that they default to a "yes" on the "Send me a free sample of the magazine" and perhaps even on the options to receive 3d party e-mail. You are safest if you carefully review magazine sweepstakes and click "NO" on all offers and be sure to click the button on the initial page that says you don't want a subscription or are already a subscriber (if it is there. . .sometimes we are able to link you to the "alternate" page which is the one that presumes you DON'T want to subscribe).
If you receive notice that you've elected to received a magazine subscription that you don't really want, visit the website for the magazine and look for the Customer Service link. There, you should be able to unsubscribe, although you may receive a message that you need to wait for a while before unsubscribing. If you click on this link: http://subscribe.hearstmags.com/circ...red/index.html
it gives you a list of Hearst Magazine websites, including links to each customer service page, where you can unsubscribe.
If you receive a magazine you don't want, there should be contact info in the magazine itself that you can use to unsubscribe. If you receive an invoice, return it with big red letters across the front that say PLEASE CANCEL!