60-day Prepaid Game Cards are available at most retail game stores for $29.95. Prepaid Game Cards are an easy way to create a new subscription or extend an existing subscription, and make great gifts.
To apply a Prepaid Game Card subscription to your account, log into your Account Administration Page at:
http://www.worldofwarcraft.com/account, and look for the Subscription options:
For additional assistance using Prepaid Game Cards, please contact our Billing & Account Services team:
by Email:
billing@blizzard.com
by Phone: 800-59-BLIZZARD (800-592-5499)
Source ---> WoW