Fans, short for fanatics, are assuredly a breed unto themselves. This -- an uneven mixture of stories about the zaniest of spectators and a bit of psychology to explain how devotion turns rabid -- is nothing to get too excited about. Here you'll meet Loudy Loudenslager, a zealous Baltimore Colt patron whose wife bakes black-walnut cakes for all the players. . . and Hilda Chester who for years used a cowbell to signal bumbling Dodger gaucheries. And then there's Detroit Shirley, the all time No. 1 ""free sampler,"" who super-balled her way toward some kind of record in the Hall of Dames. In today's voyeuristic society reading about fans, as opposed to being one or watching them, is just one vicarious step too removed from the action.