This is another of those memory aid posts. After I got tired of seeing Hewlett-Packard as the licensed organization on my laptop, I dug into the registry and changed it.
Go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion and make your changes to RegisteredOwner or RegisteredOrganization as desired. A reboot is not required. Your ProductId is there too if you want to record it.