Sorting out the options for a CNC mill system

I'm planning to get a desktop mill in the next few months and even deciding on a Taig, for example, find the combinations of motors, controllers and software a bit overwhelming. A turnkey system is a bit pricy. It would be more fun to build the system myself but I don't want to get parts only to find out they aren't compatible.

I need an "electronics/hardware version" of a book like David Benson's "Beginner's Guide to CNC."

In other words, what goes between the CNC ready mill and the PC? Most of the books I see deal with large commercial-industrial machines.