My personal favorites at this point in time
(in no particular order)

• John Irving: He creates such memorable and unusual characters, and all the emotions feel so genuine. The circumstances of his plots can be beyond believable but that’s exactly what makes them work. Start with The World According to Garp.
• Stephen Jay Gould: One of the most accessible science writers of all time and a leading paleontologist who codeveloped the evolutionary theory of punctuated equilibrium. Most of his books are collections of essays. Start with Full House.
• Charles Dickens: The names alone would make his books wonderful reads. His illustration of Victorian English life, warts and all, make them fascinating. Ultimately, it is the humanity of Dicken’s writing that wins you over completely. Start with A Christmas Carol and move quickly to Bleak House.
• Gore Vidal: A heroic American writer. His historical novels are second to none for their readability and insights into the strengths and weaknesses of American leaders throughout the ages. Start with Burr then continue through his entire The American Chronicle Series.
• Tom Robbins: Totally outrageous in every respect. A joy to read. His novels often include religious elements far outside the mainstream. Yum. Start with Jitterbug Perfume. 
• Tom Wolfe: His novels are so journalistic they seem more real than nonfiction. His journalistic books are just the opposite. Wolfe brings remarkable insight to whatever he writes about. For his journalistic works, start with Electric Kool-aid Acid Test. For his novels, start with Bonfire of the Vanities.
• Jane Austen: What can I say? Her heroines are so wonderful and the dialogue so deliciously (if politely) wicked that you just can’t resist her books. Start with Pride and Prejudice.
• Mark Twain: Possibly the best — and wisest — comic writer America has ever known. Start anywhere you want, but you must read Huckleberry Finn.
• P.J. O’Rourke: His politics aren’t mine, but his writing is so witty and his insights so keenthat I find he opens my mind. And, that’s a good thing. Start with his most recent book, as they are about current affairs as a rule.
• Douglas Adams: Some people might call him a sci-fi writer. Well,not if they’ve actually read him. What sci-fi writer would pen: “Flying is easy. Just throw yourself at the ground and miss?” Start with The Hitchhikers Guide to the Universe, but avoid the movie by the same name.