I really haven't found a single tutorial that take you from the beginning to end creating an addon. I've been reading all of them I can find and just putting the info together. Right now I've learned how to import, create & name LOD's, and what named selections are required for a weapon. I'm still kinda confused when it comes to the different shaders involved, but I'm starting to get the picture.
The best advice I can give you is this: Read everything relevant on the PMC Editing Wiki, then read it again. Next get the BI tools, download the BIS sample models. Just 10 minutes studying those models cleared up so many questions I had. Any other questions, search the forums or just ask.
As for the musket: I'll be gone this weekend, but I would like to have the model finished early next week, so I can work on the textures.