Paul,
You ought to check out the
National Muzzle Loading Rifle Association
They put out a magazine called MUZZLE BLASTS that is very informative on American frontier history, muzzle-loading, and Second Amendment issues. They also list information on the various Buckskinner Rendevous. I hope you will join.
On muzzle-loading, I recommend starting off with a percussion gun and then move up to a flintlock when you have become proficient. The flintlock rifles are harder to master, but mastery will come with practice.
I started out with a Traditions Pioneer rifle (percussion) and it shot very well, better than the CVA Hawkins I got later. The Lyman Great Plains rifle (.50 cal flintlock) shoots better than I can.
I recommend that you get a roundball mold to cast your own ball so as to save money. When you get around to buying a flintlock, learn how to knap flint.