Inexpensive CNC Projects: build your own CNC machine

Build Your Own CNC Machine (Technology in Action)

Getting Started with CNC: Personal Digital Fabrication with Shapeoko and Other Computer-Controlled Routers (Make)

CNC Robotics: Build Your Own Workshop Bot

The CNC Cookbook: An Introduction to the Creation and Operation of Computer Controlled Mills, Router Tables, Lathes, and More

Motors for Makers: A Guide to Steppers, Servos, and Other Electrical Machines

Building the KRMx01 CNC: The Illustrated Guide to Building a High Precision CNC

Getting Started with 3D Carving: Five Step-by-Step Projects to Launch You on Your Maker Journey

Programming Arduino: Getting Started with Sketches, Second Edition (Tab)

3D Printing and CNC Fabrication with SketchUp

Practical Electronics for Inventors, Fourth Edition