Bryan Mathers of Visual Thinkery created a number of wonderful images for the book. These are all openly licensed with a CC-BY license, so like the book you are free to use them yourself as long as you acknowledge the originator (Bryan).

There is an images zip file, or select from the ones below:

Specs

Spotlight sketch

Year zero sketch

Vendors sketch

Dystopian turn sketch

Cover

Title

Alchemy sketch