"Main Street," the classic novel by Sinclair Lewis, isnt just a SINCLAIR LEWIS book - its a one-way ticket to Gopher Prairie, a town so quintessentially Midwestern that even the cornstalks have an opinion on proper decorum. Follow the adventures (or misadventures) of Carol Kennicott, a city girl with dreams bigger than her new husbands medical practice, as she takes on small- town life with the enthusiasm of a squirrel at a nut festival. But beware, Gopher Prairie isnt just any sleepy to