Hi @Matt Graham ,
When I tried registering the Microsoft.DevOpsInfrastructure, the Locations were not visible:
The workaround to fetch the Locations is to use the PowerShell command below:
$resourceprovider = Get-AzResourceProvider -ProviderNamespace Microsoft.DevOpsInfrastructure
$resourceprovider.Locations
The selection of location will happen when you create the Managed Devops pool, which you can do like below:
Hope it helps!
Please do not forget to click "Accept the answer” and Yes, this can be beneficial to other community members.
If you have any other questions, let me know in the "comments" and I would be happy to help you.