Can someone give me some direction on how to implement this?

Email from Google:
Subscriptions, or recurring billing, are now available in beta
using the Google Checkout API.

If you're comfortable building your own carts using Checkout,
you're ready to implement Subscriptions by consulting the
documentation on our Beta Features page.
Each billing recurrence is a new order, so everything you've
learned about processing orders still applies. You can let us
create these billing recurrences for you with Google-Handled
Subscriptions, or if you'd like more control, you can create these
recurrences yourself with Merchant-Handled Subscriptions.

To learn more, please read our announcement on the
Official Google Checkout Blog