Reddit mentions of J.R.R. Tolkien Companion and Guide (Two Volume Box Set)

Sure. Stop me when this gets boring!

The History of Middle-earth.

The History of the Hobbit.

The Road to Middle-earth, J.R.R. Tolkien: Author of the Century and Roots and Branches, all by Tom Shippey

You should read Tolkien's Letters, too.

Other books to consider:

The LOTR reader's Companion

J.R.R. Tolkien and His Literary Resonances

Perilous Realms: Celtic and Norse in Tolkien's Middle-earth

The Keys of Middle-Earth: Discovering Medieval Literature through the Fiction of J.R.R. Tolkien

Understanding The Lord of the Rings: The Best of Tolkien Criticism

J.R.R. Tolkien Companion and Guide

If you're feeling rich, you could try to find a copy of Songs For The Philologists, a collection of poems, mostly in Old English, written by Tolkien and E.V. Gordon (I only have a .pdf copy).

I'd also read Tolkien's Beowulf criticism.

and just for fun, read Ents, Elves, and Eriador: The Environmental Vision of J.R.R. Tolkien, which is nothing to do with philology but which was cowritten by my major professor :)

Let's see, what else? Anything by Douglas A. Anderson, Verlyn Flieger or Michael Drout (especially Drout's Beowulf and the Critics and How Tradition Works: A Meme-Based Cultural Poetics of the Anglo-Saxon Tenth Century.

That's pretty much all that leaps immediately to mind, just glancing over my bookshelves, but if you search for "Tolkien scholarship and criticism" you will find much, much more. Hope this helps!

The principal biography is the authorized one by Humphrey Carpenter. (Stay away from the one by Daniel Grotta, which contains considerable misinformation.) There's also a very good book about Tolkien's experiences in WWI, Tolkien and the Great War, which I highly recommend.

Beyond that, if you want more information, seek out Hammond and Scull's two-volume J.R.R. Tolkien Companion and Guide.

http://www.amazon.com/gp/aw/d/0618391134?pc_redir=1413800510&robot_redir=1

J.R.R. Tolkien Compendium and Guide. Gives an almost day by day account of the man's life. If you can find it at the library it could be a great resource. I have a copy on my shelf and I love it. Not something I read cover to cover, but it's fun to flip through if you're a fan.

I'd also recommend Hammond and Scull 's chronology and guide it's an impressive work. And it looks like they're working on a second edition which is exciting, so you might want to wait till it comes out.

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