I picked up two books on making powderhorns. One is "Making Powder Horns, Book II" by Robert Byerly. The other is "The Book of Buckskinning II", put out by Muzzleloader Mag/Scurlock Publishing. Both are available from Track and Dixie. Haven't tried making a horn yet, but I've read thru them and seems like their instructions are clear. As for making a loading block, I've made a couple lately. Didn't use any books, just trial & error. My only suggestion is get a good look at one in a catalog/website, then make a pattern/template. I used a Manila folder and drew a "half pattern" at the fold. That way, when I cut out the pattern it was symmetrical. (I tried drawing freehand onto a block of wood and realized I have no artistic talent). Then draw the "holes" for the block onto the pattern, but don't cut them out. Just take an awl and push it thru the center of each hole. Trace the pattern on the piece of wood, then push the awl thru the hole in the pattern to make the mark on the block where you need to drill each hole. It worked for me.