If you really insist on buying on internet, here's a list for you.

1. Digital Gold by Nathaniel Popper
https://www.amazon.com/Digital-Gold-Bitcoin-Millionaires-Reinvent-ebook/dp/B00P6TZLOU

2. Cryptoassets by Chris Burniske and Jack Tatar
https://www.amazon.com/Cryptoassets-Innovative-Investors-Bitcoin-Beyond-ebook/dp/B0743MPV9R

3. Blockchain Revolution by Don Tapscott and Alex Tapscott
https://www.amazon.com/Blockchain-Revolution-Technology-Cryptocurrency-Changing-ebook/dp/B01EGYYNF8