The Chronicles of Narnia by C.S. Lewis -- While Tolkien never quite warmed up to the seven "fairy stories" written by his friend Jack (C.S. Lewis's nickname among friends and family), many readers found their way to Middle-earth by way of Narnia. Few children's books are as effortlessly engaging as these, and you can always spot a fellow Narnian-trapped-in-the-real-world by seeing how he or she responds to phrases like "farther up and farther in!" or "he's not a tame lion." Best read in the order of publication (rather than the newer "chronological" order), the Chronicles are an amalgamation of Christian themes, Greek and Norse myth, tweedy English sensibilities and medieval epic adventure.
The Prydain Cycle by Lloyd Alexander -- Based on the Welsh myths of The Mabinogion, Lloyd Alexander's somber Prydain and the things that take place there have a strong resemblance to Tolkien's Middle-earth. Although written for children in the 9-to-13-year-old range, The Book of Three, The Black Cauldron, The Castle of Llyr, Taran Wanderer and The High King are astonishingly good and survive not only the test of time but, often, the reader's passage into adulthood. Alexander's affection for his characters achieves that trickiest of elements in fiction - a real, palpable chemistry among protagonist Taran and fellow wayfarers Eilonwy, Gurgi, Fflewddur Flamm, and Gwydion. And while there is plenty in the way of battle scenes, cliffhangers, desperate situations and courage, there is also Alexander's gently witty narration and the undeniable magnetism of a story that feels like much more than "just" a story.
The Time Quartet by Madeleine L'Engle -- Snoopy wrote it on his typewriter for decades but that stolid old novel-starter "It was a dark and stormy night" is an actual opening line. It's the first sentence of one of the most original children's books of the 20th century. A Wrinkle in Time was rejected by more than sixty publishers before finding a home at Farrar Straus & amp; Giroux and winning the Newbery Medal in 1963. L'Engle handles her scientific milieu -- protagonist Meg's parents are both scientists -- with the surefooted ease of a nuclear physicist and Meg's imperfections (a quick temper, pre-adolescent moodiness) have endeared her to countless simpatico young readers. Also, in spite of the fact that the book is filled with time travel, computers, other worlds and strange, witchy women, L'Engle's vision is one in which everything that matters boils down to one fierce and beautiful thing - love.
The Song of Fire and Ice Trilogy, by George R.R. Martin -- Fans of this series love to point out the double middle initials Martin shares (perhaps affectedly) with Tolkien. But beyond both being sprawling fantasies set in elaborate worlds, that's where the similarities end. If you think Tolkien's world is far too black and white, with both evil and good appearing only in their absolute forms, Martin's books (A Game of Thrones, A Clash of Kings and A Storm of Swords) might be for you. Call it postmodern fantasy if you want, but it's a world where good doesn't always win, where you'll find yourself rooting for characters you sort of hate and where very mature doses of sex and violence characterize the action. Martin was the brains behind the cult TV show Beauty and the Beast (starring Linda Hamilton), and since his trilogy has been so popular, he is coming out with book four in the series, A Feast for Crows, in April.
The Silmarillion by J.R.R. Tolkien -- If you love The Lord of the Rings and you haven't read The Silmarillion yet, you need to -- right now. This is the backstory of Middle-earth, and it tells the tales deep in that world's ancient history. There's some creationist stuff to wade through at the beginning, but soon enough Tolkien gets down to business, with a series of panoramic tales that deliver more of the good stuff. In the old days, before the rings of power, Silmarils -- rare stones -- wreaked havoc, as everybody fought over them. Only a few of the characters you get to know in LOTR appear in The Silmarillion (Sauron, Gandalf, Smeagol), but you learn more about the creation of the rings. Peter Jackson borrowed some of the stories from The Silmarillion for his opening sequence in The Fellowship of the Ring.