Winston Churchill is at least three authors: the more famous Sir Winston Churchill who wrote history (in more than one way!), his grandson, and an American novelist. The elder Winston S. Churchill and the American met in 1901, and the British author agreed to sign his books "Winston S. Churchill." When the time comes to split them looking them both up in Wikipedia should help.
The Library of Congress headings are:
Churchill, Winston, Sir, 1874-1965 the author of the bulk of the LT titles. He wrote only one novel, Savrola, so any other book-length fiction is by the American author.
Churchill, Winston S. (Winston Spencer), 1940- the grandson, author of Defending the West; His Father's Son; Memories and Adventures. The grandson is also the editor of many of the compilations of his grandfather.
Churchill, Winston 1871-1947. the American novelist, while prolific in the early 20th C has far fewer titles in LT. These include Richard Carvel, The Crisis, The Crossing, Coniston, A Far Country, and The Dwelling Place of Light.
edited 18 April 2007

Someone has "nevered" Winston Churchill and Winston S. Churchill. If you have works by the American novelist, use the name Winston Churchill in the author box (edited May 21, 2007)