How to forward your domain's "non-www" verion to the "www" version on GoDaddy
If you bought your domain through GoDaddy, you can follow the steps below to forward your "naked" domain (without the www) to your WWW version.
1) Log in to your GoDaddy site on the home page, and click the "My Account" link
2) Click the green "LAUNCH" button next to the "Domains" label
3) Click on the name of the domain you are managing.
4) Click the "manage" link in the "Forwarding" section
5) In the popup that comes up, click "Add Forwarding" or "Edit Forwarding"
6) Type your domain name with the WWW into the "forward to" field, and click "Add". Set the other fields as pictured.
A message will pop up warning that the changes could take up to 48 hours; however, in most cases it will take much less time.