The Kojiki and the Rikkokushi are the seminal texts for the legends and history of Japan. Although, when it comes to the Shinto mythology, I do remember reading somewhere that it wasn't organized until the Yamato Clan rose to power and basically made their own nature and ancestral deities the deities over other peoples' and clans'.
For something more recent, there's The Tale of Genji by Lady Murasaki Shikibu, which is a classic and has that bygone era nobleman adventurer-explorer charm.
For more modern literature, I remember being a great fan of Haruki Murakami's stuff, especially his short story collections: After the Quake and The Elephant Vanishes.
For Chinese literature, I'm less familiar. I've read The Art of War (in graphic novel format, which I thought was pretty cool), but only heard about the Romance of the Three Kingdoms.