Being a vegetarian in Japan can be slightly hard to do since a lot of the food is seafood based. However, there are quite a few delicious vegetarian friendly dishes that one can get. A hot spot for vegetarian friendly cuisine can be found in Kyoto. Many of the temples serve just vegetarian styled foods, but the downside of eating at a temple is the cost can run up to $40 per person.
Some traditional meals that are vegetarian friendly with lots of flavor are shown below.
Vegetable Tempura, fried vegetables
Yaki Onigiri, fried rice balls
Kabocha Korroke, pumpkin croquettes
Okonomiyaki, cabbage pancakes (usually has meat, but can be omitted)
Zaru Soba, buckwheat noodles