Ha, yeah I spent a long time at work doing just what you described with Stephenson on Amazon. Lots of Gibson, who never did anything for me, and Gaiman, who I absolutely love but have read all his stuff. I have been wanting to reread American Gods though. Damn good book. Something both Gaiman and Stephenson do is instill a sense of wonder in me while I'm reading, which comes from a deep appreciation for the author's creativity and the immensity of their accomplishment. The Baroque Cycle, in this sense, is the most enjoyable series I've ever read, though I'll always have a special place in my heart for Vandermeer's Ambergris novels (time for a sequel to Shriek Jeff).
I've read and enjoyed the first Discworld novel, as well as the book about the apocalypse Pratchett and Gaiman cowrote. Christopher Moore is a new name to me, looks fun.
Any comments on the Culture novels by Iain M. Banks?
EDIT: Dan, just read synopsis for two Tim Powers novels: "Declare" and "The Drawing of the Dark". That is what I'm talking about! Can't wait to get my hands on one of these.