Shdoan Web Site
https://www.shodan.io/

Shodan Help
https://help.shodan.io/

Shodan Account
https://account.shodan.io/

Shodan Command-Line Interface
https://cli.shodan.io/

Shodan Paid Plans
https://account.shodan.io/billing 

Complete Guide to Shodan, by John Matherly (LeanPub book for $5)
https://leanpub.com/shodan 

Shodan Snippets Collection
https://snippets.shodan.io 
