Welcome to the forum. Your post is going to save you some money.
First thing to know is Tandy is all about newcomers. They smell blood in the water (lived it).
Everything they have can be bought better and cheaper elsewhere. I don't mean to bash Tandy because I started there myself. They do provide a large chain of brick and mortar storefronts to get beginners started, but the advantages pretty much end there.
Springfield Leather is a good place to start for a beginner. The owner Kevin, used to run Tandy stores.
You're going to find better service and leather there.
More folks will chime in on cheaper places to obtain leather, but as a hobbyist you will be paying retail anyway.
Your projects will dictate your leather purchases. You will need veg tan leather for carving.
As for tools, a straight edge, a good square and a razor knife will make your cuts. As far as carving tools (and your cry once attitude) a person could do a lot worse then Barry King tools. He makes quality stuff that will spoil you. If you look on his site he actually has sets of tools. The set runs 500.00 of I remember correctly. That sounds like a lot, but they will out live you, and probably your kids.
As far as edges go. There is a really good review of the ranch hand quick change edger. I will be buying one post haste. It runs 45 bucks at weaver and includes five different blade sizes with it. The man who did the review is very well respected around here. That's Nigel @ armitage leather. Look him up on YouTube. His saddle stitch video is often referred here as well.
Speaking of videos, Springfield leather also has a lot of helpful videos as well. And Kevin is really entertaining.
I hope you find these tips cost effective and helpful.
From one newb to another,
Keep having fun.