Oh lord. This could go on forever. Let's see...
Harry Potter by J. K. Rowling, Dies the Fire, and the rest of the Change series by S. M. Stirling, The Heralds of Valdemar series by Mercedes Lackey, The Vampire Earth series by E. E. Knight, the Dragon Riders of Pern series, by Anne McCaffery, The Sight by David Clement-Davies, The Abhorsen trilogy by Garth Nix, Narnia by C. S. Lewis, and many more that I shall probably talk about later, when their names pop into my head.