The iconic silent movie comedian Buster Keaton was not only a legendary Hollywood figure; he also had an impact on the broader culture (Samuel Beckett, for one, acknowledged his debt to him). Time, then, for a definitive biography, and that's what Canadian actress and playwright-turned-author Elieen Whitfield plans, in a book just signed, for a best-bid offer, by Victoria Wilson at Knopf. There's a quite a backstory there. Whitfield's first book, her 1997 study of Mary Pickford, was commissioned by a small Canadian publisher, Macfarlane Walter & Ross, but her advance was so small that she had to struggle with part-time jobs to make ends meet in the years it took her to write it--and the publisher was unable to interest a major American publisher in it. Eventually it was taken by the University Press of Kentucky, made several "best books" lists and won a feature-length rave review in the New Yorker, so this time out Whitfield's agent, Jackie Kaiser at Westwood Creative in Toronto, did not have to shop so hard south of the border. Simon & Schuster and FSG both bid on it, but Knopf's Wilson had the best offer, for U.S. rights. Canada is probably spoken for, but Kaiser has the rest of the world.