The collecting of elongated coins is a branch of numismatics. Elongated coins are also categorized as exonumia.
The first time I saw a penny pressing machine was in Cabazon, California in the gift store near the life-sized dinosaurs. I was hooked, and I've been collecting them ever since.
Welcome to my pressed penny collection from my travels across the USA and/or found in geocaches!
The Elongated Collectors [TEC]
https://tecnews.org/
Cleaning Techniques for Pennies
http://www.pennycollector.com/cleaning.html
Penny Press Machine Locations
http://209.221.138.252/AreaList.aspx
or https://pennypresses.net/
Storage: Sleeves, Books, Supplies
https://www.amazon.com/