Where does ''Fight Club'''s author find his twisted inspiration? This grab bag of barely edited nonfiction pieces called ''Stranger Than Fiction'' holds the soporific answer. The topics amble from a depressing hospice to a sweaty Greco-Roman wrestling match; even a Juliette Lewis portrait lacks decent repartee. Chapters about Palahniuk's murderous grandfather and his fondness for Brad Pitt's lips should sate biographical completists. Everyone else will wonder why Palahniuk is more obsessed with his first novel than his next.