It is very satisfying, it also means I can get it just the way I want without spending too much money.
The stitching's not so hard, but you do have to make holes first...
I drill the holes for the leather, after clamping the edges together. A lot of people glue the edges as well. I used a 0.8mm drill bit in a modelmaker's vertical drill press that I used to use for drilling circuit boards.
The other way (more traditional) is to push an awl through the leather to make the initial hole. This is arguably better as it doesn't remove leather, just pushes it aside. So when the stitches are in, the leather can close up again, sealing the hole. It's much harder to do with thick lumps of leather though, and certainly harder when you don't have an awl!
Either way, it's best to mark the stitch points first with either a stitch iron or a stitch wheel. The stitch wheel is the only leather tool I have apart from the needles. The iron has a row of pins in a line so is great for straight lines. The wheel is a toothed wheel on a handle that you run along the line you want to stitch. Then you make the holes where the marks in the leather are.
It's also best to groove along the stitch line, so that the stitches are recessed. There's a special tool for this but I used a screwdriver.
The holes are still quite narrow so I used a pair of pliers to push and pull the needles through the holes. I use two needles, one on either end of a single piece of thread, and push each one through each hole, from opposite directions, so you get a stitch on each side.
The hardest part is threading the darn needles! The thread is quite thick and multi-strand - it really doesn't want to go through that little hole. My technique? Put a bit of glue on some paper, fold it, and squeeze the end of the thread through the glue. It seals the ends of the strands and leaves a thin tail that you can get through the eye. The only alternative I've found is to ask my wife to do it!
