Help:Finding the ISBN Number of a Book

The Library of Congress online catalog would seem like a good place to get the ISBN number of a book. However, the LC site is sometimes so busy that it blocks additional users from searching. The following, then, are some alternate databases to use in order to get ISBN numbers. Remember, however, that none of the databases below will show an ISBN if the book does not have one.


 * OCLC/Worldcat
 * Amazon
 * Book Butler