For anyone getting into real shaving here is a brain explosion.
In many countries of the world there are artisan soap makers. It is just sodium and potassium salts of fatty acids so is quite easy to make once you have your fats/oils and some lye. But to make good soaps takes excellent ingredients, a knowledge of chemistry, creativity and lots of trial and error.
Shaving soaps are a lot different to bath soaps, the job they are being asked to do is completely different, they need to lubricate and to build up a big and sustainable lather. Despite this many artisan soap makers have thrown their energy into shaving soaps and as a result the range available out there is simply stupendous. You could write several books about them.