Fiction and Verse
1937 - The Hobbit
1949 - Farmer Giles of Ham
1954-55 - The Lord of the Rings
1954 - The Fellowship of the Ring - Lord of the Rings, Part One
1954 - The Two Towers - Lord of the Rings, Part Two
1955 - The Return of the King - Lord of the Rings, Part Three
1962 - The Adventures of Tom Bombadil
1964 - Tree and Leaf - Contains "Leaf by Niggle" and "On Fairy Stories"
1966 - The Tolkien Reader
Contains The Homecoming of Beorhtnoth Beorhthelm’s Son, "On Fairy-stories", Farmer Giles of Ham, Leaf by Niggle, and The Adventures of Tom Bombadil
1967 - Smith of Wootten Major
Nonfiction and Translations
1925 - Sir Gawain and the Green Knight (edited with E.V. Gordon)
1937 - Beowulf: The Monsters and the Critics
1962 - Ancrene Wisse: The English Text of the Ancrene Riwle
Posthumous Publications
1975 - Sir Gawain and the Green Knight, Pearl, and Sir Orfeo (translations)
1976 - The Father Christmas Letters
1977 - The Silmarillion (ed. Christopher Tolkien)
1980 - Unfinished Tales (ed. Christopher Tolkien)
1981 - The Letters of JRR Tolkien (ed. Christopher Tolkien & Humphrey Carpenter)
1982 - Finn and Hengist (ed. Alan Bliss) – A collection of Tolkien’s lectures.
1982 - Mr. Bliss
1983 - The Monsters and the Critics (a collection of essays)
1983-1996 - The History of Middle-earth (Twelve Volumes)
Book I - The Book of Lost Tales, Part One (1983)
Book II - The Book of Lost Tales, Part Two (1984)
Book III - The Lays of Beleriand (1985)
Book IV - The Shaping of Middle-earth (1986)
Book V - The Lost Road and Other Writings (1987)
Book VI - The Return of the Shadow (1988)
Book VII - The Treason of Isengard (1989)
Book VIII - The War of the Ring (1990)
Book IX - Sauron Defeated (1992)
Book X - Morgoth’s Ring (1993)
Book XI - The War of the Jewels (1994)
Book XII - The Peoples of Middle-earth (1996)
1992 - Pictures by JRR Tolkien (text by Christopher Tolkien)
1998 - Roverandom
2007 - The Children of Hurin
2007 - The History of The Hobbit (ed. John D. Rateliff)
A collection of Tolkien's early drafts of The Hobbit, with commentary by scholar John D. Rateliff. Similar to books VI-IX of The History of Middle-earth which explored the early drafts and writing of The Lord of the Rings.
2008 - Tales from the Perilous Realm
2009 - The Legend of Sigurd & Gudrun
Found here-
http://www.tolkien-online.com/books-by-tolkien.html
But I know there's more Middle-Earth stuff than that.
1937 - The Hobbit
1949 - Farmer Giles of Ham
1954-55 - The Lord of the Rings
1954 - The Fellowship of the Ring - Lord of the Rings, Part One
1954 - The Two Towers - Lord of the Rings, Part Two
1955 - The Return of the King - Lord of the Rings, Part Three
1962 - The Adventures of Tom Bombadil
1964 - Tree and Leaf - Contains "Leaf by Niggle" and "On Fairy Stories"
1966 - The Tolkien Reader
Contains The Homecoming of Beorhtnoth Beorhthelm’s Son, "On Fairy-stories", Farmer Giles of Ham, Leaf by Niggle, and The Adventures of Tom Bombadil
1967 - Smith of Wootten Major
Nonfiction and Translations
1925 - Sir Gawain and the Green Knight (edited with E.V. Gordon)
1937 - Beowulf: The Monsters and the Critics
1962 - Ancrene Wisse: The English Text of the Ancrene Riwle
Posthumous Publications
1975 - Sir Gawain and the Green Knight, Pearl, and Sir Orfeo (translations)
1976 - The Father Christmas Letters
1977 - The Silmarillion (ed. Christopher Tolkien)
1980 - Unfinished Tales (ed. Christopher Tolkien)
1981 - The Letters of JRR Tolkien (ed. Christopher Tolkien & Humphrey Carpenter)
1982 - Finn and Hengist (ed. Alan Bliss) – A collection of Tolkien’s lectures.
1982 - Mr. Bliss
1983 - The Monsters and the Critics (a collection of essays)
1983-1996 - The History of Middle-earth (Twelve Volumes)
Book I - The Book of Lost Tales, Part One (1983)
Book II - The Book of Lost Tales, Part Two (1984)
Book III - The Lays of Beleriand (1985)
Book IV - The Shaping of Middle-earth (1986)
Book V - The Lost Road and Other Writings (1987)
Book VI - The Return of the Shadow (1988)
Book VII - The Treason of Isengard (1989)
Book VIII - The War of the Ring (1990)
Book IX - Sauron Defeated (1992)
Book X - Morgoth’s Ring (1993)
Book XI - The War of the Jewels (1994)
Book XII - The Peoples of Middle-earth (1996)
1992 - Pictures by JRR Tolkien (text by Christopher Tolkien)
1998 - Roverandom
2007 - The Children of Hurin
2007 - The History of The Hobbit (ed. John D. Rateliff)
A collection of Tolkien's early drafts of The Hobbit, with commentary by scholar John D. Rateliff. Similar to books VI-IX of The History of Middle-earth which explored the early drafts and writing of The Lord of the Rings.
2008 - Tales from the Perilous Realm
2009 - The Legend of Sigurd & Gudrun
Found here-
http://www.tolkien-online.com/books-by-tolkien.html
But I know there's more Middle-Earth stuff than that.