Roy Blount, Jr. Anything and everything he puts out, although I definitely like some of it more than the rest. I’ve still got his recent biography of Robert E. Lee, just waiting for me to get up enough interest to read it.
And I guess technically J.K. Rowling, but I wouldn’t instantly buy a non-Harry Potter book by her (in fact, I’d probably avoid it) so I don’t know if she counts.
for me it’d be:
Neil Gaiman: same as a lot here, my fav is Neverwhere
William Gibson: haven’t tried his last one, but until now i love all his books
Robert Jordan: yes i know how awful the last was, but i still have faith
Bernard Werber: french author, he wrote “The Ants”, “Empire of the Ants” “Revolution of the Ants”, “Les Thanatonautes”, …next one is due the 1st of actober
Maurice G Dantec: french too, wrote “Red Siren” “Babylone Babie” “Roots of Evil”
You may want to go The Heinlein Society real quick then. 
So I take it you already have Callahan’s Con?
Lok
Grahrg, nine day-old news, and I post it one minute late?
Actually, I already posted it once here.
Lok
Kurt Vonnegut– except he’s said that he is through writing books.
So that only leaves Martin Amis– maybe the best ever.
Lok, how coud I have missed that thread? Oh well.
I’m afraid my own list at this point would merely be repeating what every one else has said.
Hmmm.
Has nobody mentioned Bruce Sterling or William Gibson yet? And the Neal Stephenson fans night enjoy books by Stephen Bury 
Yeah, I’m in an old-school-cyberpunk state-of-mind right now.
Sy, I forgot to mention Jules Verne. Any time I see something of his I don’t Have, I buy it.
Also Sir Richard Francis Burton
Thanks, Fionn. I’ll definitely check those out.
May I use this as a sig line? It’s classic, truly classic.
Elinor Lipman I like her humor.
Kent Haruf Gorgeous, spare writing
Maeve Binchy So I like books that make you feel good and have happy endings? Stop snickering!
The latter says she’s retired, although I don’t believe it. I sit around drumming my fingers angrily waiting for the former two to write something new. Actually, I just got the new Lipman for my birthday; can’t wait to crack it.
Dang! He’s on my “buy on sight” list, but I haven’t seen this one yet. Must… resist… urge… to run out to bookstore NOW.
Tim Powers and Gene Wolfe are two more authors I snap up everything instantly from.
Roger Zelazny used to be. (I mean, he still is, but he hasn’t written anything lately. And if ever there were an author who would actually come back from the dead to write another book, I believe it would be Zelazny.)
(I see that Scumpup mentioned two of these as well.)
I can’t believe no one mentioned Jonathan Carroll!!! I am attempting to purchase all his books in 1rst editions, US and Britain.
Also on the buy everything they write list.
Joe Lansdale
Neal Stephenson
William Gibson
Larry McMurtry
Sharyn McCrumb
Martin Cruz Smith
Mark Helprin
David L. Martin
Anne Rice
Paul Theroux
And as someone else said,…I’ll remember a few more once I hit submit.
Bahaha. Of course you can.
Lois McMaster Bujold
Stephen Brust. Ryujin was wrong, I read and loved To Reign in Hell
And I’m currrently ripping through Laurell K. Hamilton
feeling very pedestrian in my choices but oh well…
JD Robb
Janet Evanovich
Banana Yoshimoto (I just love her.)
Susan Mallery
Julia Quinn
Sujata Massey
Cresent Dragonwagon (she has a wonderful vegi cookbook out as well as fabu childrens books)
JK Rowling
oh and several others that I just can’t think of right now but go into spazfits when I see them on the shelf…
Cats…
Jose Saramago is the newest addition to my list of must-reads, after reading only two of his books. Not the easiest author to read (he has a very unique style), but well worth the effort. I first read All the Names, which was interesting, and The Stone Raft, which was positively stunning. Next up, Blindness.
Other than that, some old standards of mine…
Alan Lightman - Einstein’s Dreams is his best, but all his other novels are good as well, and his science writing is wonderful. Looking forward to reading Reunion, his newest.
Stephen King - Occasionally disappointing, but his good books outweigh his bad ones by far. And heck, I’ve been reading him since I was 10 or so. I’m just finishing a beginning-to-end re-read of the Dark Tower series, and I am once again absolutely enchanted with it.
Dan Simmons - Able to write well in any genre, and unfailingly fun to read. I just convinced the sci-fi book club I’m in to read Ilium*. I’ve read pretty much everything else of his.
Clive Barker - Again, sometimes disappointing, but Abarat renewed my faith in him.
Neil Gaiman - What more needs be said?
Douglas Adams - He can make me laugh even though he’s dead. That takes talent.
Margaret Atwood - I always drift back to her books, and I’m almost always pleased when I do.
I’ll buy anything by P.D. James as soon as it’s published, only I’m not too sure how many more she’ll be writing.
Me too. For the last few books she seems to have had a bad case of ‘contractually obliged’ or ‘couldn’t care’. Her last book was published in hardback last year, and paperback a week or so ago, and I suppose I will pick it up sometime or other.
Terry Pratchett
Stephen King
James Thurber
Spider Robinson
Robert Asprin
Philip Dick
Lisa Scottoline
Oscar Wilde