Hands down the best Japanese cookbook I've come across are (all) the books by Harumi Kurihara. The entry book would probably be Everyday Harumi
. It focuses on everyday Japanese food that tastes epic and does not have the silly and naïve sushi-focus that a lot of "Japanese cookboks" have. Harumi holds your hand and breaks it all down to the level of how to cut and prepare things (example: put the sliced abourgine in a bowl of water for a while to avoid bitterness before cooking). The ingredients are not crazy. The fresh ingredient are mostly things you can find in most well stocked places. Mirin, rice vinegar, kombu, silken tofu and other ingredients probably require access to a city or internet purchase.
Being a vegetarian since a few years back I've tried finding a book of equal splendor, but it's hard. There are definitely a number of great vegetarian recipes in the Harumi books and some that can easily be converted by taking a few things out and changing the stock to Kombu stock and so on. I really wanted the Kansha book
to be a great and inspirational Japanese vegetarian cookbook, but it is slightly intimidating and uses a lot of hard to source fresh key ingredients (at least this is what I remember). It does teach a few key ideas about cooking vegetarian Japanese food. I should really revisit it soon! Regardless, I still think that the Harumi books are a great introduction to learning the basics of Japanese cooking.
Learning a new kitchen it is always a good idea to find food being prepared by people of that culture on Youtube and soak up the general underlying pattern. That has definitely been a great help for me when it comes to indian cooking