Here’s the essential clue. In order to include a file in the subfolder (fonts in this case) of a library you must first include a file in the primary source folder, otherwise the Arduino IDE will not find the file in the subfolder. So now we know that the library contains a file named glcd.h, a subfolder named fonts that contains a file named SystemFont5x7.h.
A search finds quite a few of these libraries but the parent of all of then is this one:
There are a couple downloads available and I really don’t know which is which.
There is also a Playground page for the library:
Now you will notice that it’s stated on both those pages:
This library is no longer being maintained by the authors and has not been updated since December 2011. This library does not work with newer Arduino IDEs like the latest 1.0.x releases as well as 1.6.0 IDE and beyond since the newer IDEs use updated AVR gcc tools and GLCDv3 library uses code which is not compatible with the newer AVR gcc tools.
If you are ok with a GPL 3.0 licensed library (your project is open source) openGLCD is an alternative which is compatible with GLCDv3 and is being maintained.
That library does contain a fonts folder with the SystemFont5x7.h. I notice in the wiki is mentioned that library can be configured for GLCDv3 library compatibility mode so it may be quite simple to use your code with the newer library.
This is the problem with books. The just can’t keep up with the rapidly changing world of technology. If the book doesn’t at least give a URL where you can find the glcd library that’s not a good sign of quality work.
Basic/SystemFont5x7.h at master · esp8266/Basic · GitHub
MicroView-Arduino-Library/font5x7.h at master · geekammo/MicroView-Arduino-Library · GitHub
has any Clone or download button I can see.
I already explained this to you. You won’t see the button when you’re in a subpage of the repository. You need to navigate up to the root page of the repository. The easiest way to do that is to click the repository (not user) name in the top left corner of the screen. For example in the first of your links you would click on “Basic”. Then voila, you have a “Clone or download” button.