Navigate with your browser to the Library of Congress website. At the homepage, select the "Researchers" category, which is on the upper left of the page.
On the "Researchers" page, look for the "On the Web" section on the lower right of the page. You will see "LC online catalogs." Click on this heading.
This is the main search page for the Library of Congress. Select the appropriate search form and enter the title of the book for which you are searching. If you have a copy of the book, an alternate way to search would be with the ISBN (International Standard Book Number). You can also search by author or request a specialty search by a Library of Congress librarian.