Book availability and pricing?

[Nathan Gesner]

A couple questions about the book store. 

1. Why are books only available in audio or digital format in your store but available in paperback at Amazon? An example would be "Finding and Funding Great Deals" by Anson Young
2. Why are your books so much more expensive? A digital version is available for $19.00 but it's on Amazon for $9.99. Your paperback version, when available, is $24 and on Amazon it's $16.99.

I want to support your site but I'm a fairly frugal shopper. Is there any benefit to the author (or me) if I purchase through your web site?