Oo...a lot of people read some of the same stuff I do! Terry Pratchett (Yay Discworld!), Patricia Kennealy (Yay Keltiad!), Douglas Adams (Hitchhiker's guide and Dirk Gently), and Robert Heinlein (Mostly the Future History novels and some of the short stories as well) are big favorites of mine, as are Mercedes Lackey (The Valdemar chronicles) and Isaac Asimov (The Foundation books).
A few more of my favorites: Jane Austen, Alexandre Dumas pere, Langston Hughes, Shakespeare, Mary Jo Putney, Alice Walker, Zora Neal Hurston, and Tom Stoppard.