Hey @brickbogh,
Thanks for posting this question on the Apple Developer Forums!
I have also been unable to find any resources on how to get started with the discussed Enterprise API. I filed the below Feedback asking for additional information on when it would be made available and where the documentation will be hosted.
FB14080042
The Enterprise API is also referenced in the Apple Seed for IT program if you have access to it inside of the "What's New for IT" documentation, but there is only a single paragraph of information with no technical information.
Hopefully this shows up soon so that developers can start using it!
Happy coding!