Fred Michaelson writes:

Great question! For those who haven't seen rubbings, they're actually very easy to make yourself, assuming you can still find a pencil and blank piece of paper in this digital age. Give it a try! Lay the coin on a flat surface and put the paper over it. Now hold the pencil flat, nearly parallel with the paper. Gently rub the business end of the pencil (the graphite, or "lead") back and forth across the paper directly on top of the coin. Slowly an image of the coin will appear.

Practice your technique a few times and soon you'll be a pro. Back in the day numismatists often kept notebooks of rubbings of their coins as a record of their collection. In fact, when I liquidated a fellow numismatist's collection several years ago, the most valuable item turned out to be a book of rubbings - at $2,000 it sold for almost twice what the most valuable coin brought.

Rubbings don't damage the coin (at least, not circulated ones). They're fragile because the graphite can smudge if you're not careful. But in the days before scanners and digital cameras, when photography was slow and expensive, rubbings were a great way to record a collection, and still work in a pinch.

I found these instructions online:
www.ehow.com/how_4481075_do-coin-rubbing-paper.html
www.primeradicals.ca/math-mentors/activities/coin-rubbings/
www.blogmemom.com/art-math-activities-coin-rubbings

As for the Guttag book, these images look to me to be woodcuts. An artist would engrave these in a block of wood (in reverse), and the block would be inked to print the image on the page. They may also have been done in another medium, - perhaps an E-Sylum reader can provide more information.