If I were you I would look around for a local BP club, or a weekend woods shoot. Then take your rifle with you and ask a couple of older guys to take you through the shoot with them. I am positive you can find a couple of guys that would be more than glad to share with you their knowledge, and even some of their powder and round balls. Heck you could offer them a few bucks for their materials, but I doubt if most of them would take your money.
You can learn alot from older fellows at shoots like that. And most are more than willing to help beginners. Regardless of age. Tom.