You can spend a lot of money on leather tools as is true with any hobby (or profession). I have quite a few leather tools that I've procured (mostly from Tandy Leather Factory) over the years. You can also look on eBay for used tools. The tools shown aren't all that I have but are the ones I use the most. You can "get by" in the beginning with just some basic tools such as a utility knife, straight edge, makeshift awl, stitching needles. But as you expand in your leather working you'll definitely want to get more tools. This will greatly improve the fun and quality of your work. You'll also need sponges and rags for dyeing. A cutting surface is essential. I have 4 plastic kitchen cutting boards screwed to my worktop for cutting. And most definitely a solid work surface.
Get a couple of books to look through too. The ones shown are my favorites ( available here ) The first one Leathercraft Tools how to use them, how to sharpen them is the most useful for beginners. You can get these as E-pubs or get a hard copy. I first bought E-pubs then a year later bought the real book.
You'll need a nice piece of veg-tanned leather about 7-9 oz. (that's the thickness) I used about 8 sq. ft. with the waste