If you like fantasy/sci-fi, Dragonlance series, and Salvadore's Forgotten Realms series (Icewind Dale, Dark Elf, Legacy of the Elf, etc.) are good. Also if you don't mind reading longer books, I would suggest Jordan's Wheel of Time series, although it's kinda of long but it's good. The only sci-fi books I read are the Star Wars books, they're okay...