1.) Click on the "My Account" link on the top navigation bar.
2.) Login using the name and password you used when you first created your account.
3.) Click the link near the bottom of the page that says "Subscribe or unsubscribe from newsletters."
4.) Check or uncheck the box or boxes of the newsletters you wish to modify.
5.) Click the Continue button.
6.) You should be taken back to the "My Account" page with a message that says "Your newsletter subscriptions have been successfully updated."