And if you like Douglas Adams you'll like Terry Pratchett. Best British satire around, and he's prolific, too! Guaranteed not for the easily offended, however. Or for those who think Harry Potter is a witchcraft manual, as witches and inept wizards are featured prominently.
The Discworld series! Especially "Mort" and the other Death books.
I hope I don't get flamed for saying this but Carl Hiaasen is a knee-slapper as well (his fiction, such as Sick Puppy, not his columns)
Terry Pratchett - I'll check next time I'm at the library. And I never did think that Harry Potter books were witchcraft manuals!