"My sister's boyfriend knows a family who . . ." "One of my wife's colleagues has a friend who knows someone who . . ." "This is a true story that was forwarded to me by. . ." "This is not a joke!"   In this lively and engaging book, the nation's foremost expert on urban legends explores the spontaneous germination of these bizarre yet plausible narratives that play on the absurdities and prey on the fears of modern life.   Through voluminous correspondence from readers of his books and syndicated newspaper column, Jan Harold Brunvand has become something of a clearinghouse for evolving versions of urban legends. Here he looks in detail at a dozen rampant and long-lived examples of this vigorous category of contemporary folklore, tracing their histories, variations, sources, and meanings.   Brunvand tracks the various permutations-by fax, by e-mail, by newspaper, by word of mouth--of such legends as "The Red Velvet Cake," "The Brain Drain," and "The Baby Roast." He points out their common elements--notably, their insistence on the truth of the story and their attribution to a "friend of a friend." His son Erik Brunvand, an associate professor of computer science at the University of Utah, contributes his own view of computer hacker legends traded across the Internet.   Captivating and thought-provoking, The Truth Never Stands in the Way of a Good Story pins down the qualities that give urban legends their air of authenticity and make them hard to believe yet impossible to dismiss. For those interested in popular culture and current events as well as those wary of being taken in by false information, Brunvand's book reinforces his most basic piece of advice: "Don't believe everything you hear."