Ok.. I should have checked xbox.com first.
What Happens After the Trial Period?
Unless you cancel your subscription before it ends, you will automatically renew to the currently selected renewal subscription type at the then current price, which is viewable in the Account Management section of the Xbox Dashboard. For information about canceling your subscription and the refund policy for your subscription, please see
http://www.xbox.com/live/accounts.
If you choose to renew your subscription, you can use the Xbox Live Dashboard to renew your subscription for 12 months. You can also purchase a Starter Kit or a 12-Month Subscription Card to receive 12 additional months of Xbox Live service after your two-month free trial ends.
If you do not want to continue your Xbox Live subscription, you can cancel at any time by calling 1.800.4MY.XBOX.
Look for specially marked copies of Xbox Live titles in stores now for your two-month trial subscription.
So, where would I enter my 12 month subscription code? Is there someplace in the Xbox live section of the MS dashboard?
I'll go look.