Hi Beth,
In Method for QBO, the field services app is called Scheduling & Invoicing. There are some minor differences between the apps, but the overall functionality is the same. The app can be added from the same place as the field services app in Method for QBD. Just navigate to Customize > My Account > Add Apps from the Method Application Library > Scheduling & Invoicing and select add this app….
I hope this helps.
-Audisho