Selling books direct, using PayPal and BookFunnel (to deliver)

Hi, I'd like to sell ebooks directly to readers from my website (upgraded to Commerce shortly), have them pay through PayPal (or another credit card processor), and have the ebooks delivered through BookFunnel. 

Is there a step-by-step explanation of the process? Has anyone done this? What are the pitfalls should I look for? Anything you can offer will be greatly appreciated. 

Bump?  Is this a possibility? 

Ya, like is anyone going to answer this question? I have the same idea; to sell ebooks through squarespace and use bookfunnel to deliver them in order to take advantage of their e-reader app and other things. I can't find any real info on this anywhere.