Hi Don Ferris (dferris),
you can find it in your Microsoft Volume Licensing Service Center (Volume Licensing Service Center (microsoft.com)) account.
If you don't have access to your VLSC account, you can contact Microsoft support (Global Customer Service phone numbers - Microsoft Support) for assistance. They will ask you to provide some information to verify your identity and ownership of the license, and then they can help you retrieve it.
Hope it helps.
Best regards,
Lei