Wil, your site (even the checkout page) doesn’t appear to be secure (in the HTTPS mode). I’m loathe to put in my details in an unsecure page. Besides, I don’t understand why paying through PayPal (which would require me to log in to my PayPal account anyway) should at all need my details at your website. Can you please have this fixed?
Meanwhile, to read the eBook, I am more than willing to PayPal you the $5 (using any email address of your choice), and you can send it to me via email or any other means. Would that work?