Lyman is a very good brand but do not limit yourself. Look at Thompson Center Arms as well. I have had very good luck with one of their Hawken models. Check out the National Muzzleloading Rifle Association at http://www.nmlra.org
They may have a list of local muzzleloading clubs. Also look at their link called "visit Friendship". It is a large farm in southern Indian where the hold by-annual national shoots and have a 2 week trade fair in the summer.