Google checkout invoice through API

I am 开发者_如何学Gotrying to find a way of sending email invoice via google checkout's API (and also in PayPal) I can't find how. or at least how to generate a new order (money request)

thank you

From: http://code.google.com/apis/checkout/developer/Google_Checkout_Comparison_Part_I.html

Requesting Payment by Email Invoices What is it? Email invoicing lets you sell without an online store. Buyers can place orders from you by phone, fax, email or other offline means; then you send email invoices from the Merchant Center to the buyers requesting payment. Email invoices contain a personalized message from you regarding the requested payment as well as a "Pay now through Google Checkout" link. When buyers click this link, they are brought to Google Checkout where they can complete the payment process. Best for: Use this option if you don't have or need an online store. Time required: There's no setup — just open a Google Checkout merchant account and you can immediately start sending invoices. Technical skills required: None. Just Internet access. Demo: Email Invoice and Wizard (requires sign-up) Processing Orders: (Part II) Once orders start coming in, use the Merchant Center to charge orders and update order status. Next Step: How to request payments by email invoices

From what I've seen, looks like they don't have a way to do this through an API. Hopefully someday they will, but for now I think I'll have to create my own email with a link to my own page that sends them to google checkout via a custom Buy It Now button.

It's too bad - it'd be so simple to just be able to call send_email(name, email, amount, message) and have it be the same as logging in & doing it through the Merchant Center.

I do understand the rationale a little - if you're capable of creating an automated invoicing system that can call a google API to send emails, then you should also be capable of creating a link, custom button, and letting the user checkout that way. I still want it though - I'm lazy.

Can you submit the form data in the way that the google checkout portal does? then it would authenticate and autofill the form?