The rifle you buy should be predicated on your own gut feeling, balanced by what you can gather in quality reviews in places such as here.
The best book for a new shooter, in my opinion, is the Lyman Handbook of Black Powder. It has the basics for beginners, the procedures to gain confidence and skill and a lot of information on different guns and loads. After you ahve digested that a bit, you can move on to Sam Falada's Blackpowder Handbook.
Join in the sport and enjoy "shootin' dirty."
Pops