Hey rungreen,
To your question:
At this time GoogleŽ Checkout is not integrated with Real-Time Shipping Methods. To help increase the usability of GoogleŽ Checkout a new option has been added for Custom Shipping Methods, "Hide in Cart". When this option is selected for a Custom Shipping Method, it will only be available to your customers using GoogleŽ Checkout.
To access this new option: log into the Admin Panel and go to Checkout >> Shipping >> Shipping Manager - Custom, from the "Sales Manager" section.
This information can be found at this url:
Hide Custom Shipping Method in CheckoutThanks!