Tolkien's books about middle-earth

The Hobbit The Lord of the Rings> The Silmarillion

The Book of lost Tales (Part 1+2)
The Lays of Beleriand

The Shaping of Middle-earth
The Lost Road (and other writings)

Return of the Shadow
The Treason of Isenguard

the War of the Ring, Sauron Defeated,
Morogoths Ring, The War of the Jewels,

The peoples of Middle-earth
The Adventures of Tom Bombadil. Unfinished Tales