I would get a couple of the kits, like the cell phone holster or wallet or something else you could use. These usually come with some thread, needles and snaps etc. you can make a pattern of the pieces and then tool or stamp away. The holes are already punched so sew or lace it up. The holes are too big but this means if you screw up lacing ( and you will) un lace it and start over. If you screw up tooling buy a piece of leather trace the pattern out and start over. Do this a couple of times and you will start to get the hang of it. There are a bunch of books at tandy and other places on sewing, lacing, and everything else. Then you can see what you need to get to do the type of tooling or projects that you want. Don't forget to post questions and pictures on here.
Good luck and welcome
David