How costly is it?
Depends. Copper is expensive. The 24x24 copper plate I purchased for this project was $300. Access to a press isn't the most easy thing in the world either. Here I accomplish the feat by taking a class (~$250). Engravings/etchings/drypoint can be done on other cheaper materials though, but I've only used copper so far.

Glad to see some interest in a tutorial. Makes it more likely to happen one of these days.