Instructions
Perform an anti-virus scan on your computer to eliminate any malicious software so that once your account has been restored it is not susceptible to further attack.
Change the password on the email account that is associated with your "World of Warcraft" account. This will ensure that if someone hacked your email account as well, they will not have access to the confirmation email sent at the end of the recovery process.
Go to the Blizzard Account Recovery site.
Start the recovery process by clicking "Begin Account Recovery" at the bottom of the page.
Follow the instructions until the recovery process is complete.