The core components of the mountain banjo I’m making are now assembled. Fitting and stretching the goatskin was a bit of a challenge. I wanted a snug fit and my hole was a smidge tight, causing me some grief. Also, I used a piece of stove-pipe that snaps together for stretching the goatskin, and I realize this isn’t quite ideal because it means the rim isn’t consistent all around. Still, I think it will work out OK. I’ve left it to dry and hopefully, the skin will tighten up nicely. There is still plenty of work to do before I can string and play this instrument, but it’s coming along.
27th Street 
Goatskin is good but the genuine product would be groundhog skin. Sadly you cant buy them and the only way to get one is from a groundhog.
Goatskin is not all that hard to get. You can order it from drum or other instrument supply places. Yes, I’ll do a video demo when it’s ready.
I would imagine that goatskin is not the easiest component to source. I trust there will eventually be video demonstrations on the finished product?