If you know of a library with a special collection that is currently not part of the Google search, ask your librarian to send an e-mail to: books-support@google.com. If you are the person in charge of a library collection, send Google the following information:
The name or title of the collection
The size of the collection in number of works or archived items
Description of the unique or specialized content
How much of the collection is already digitized
Languages used within the collection
For additional information about this process and what libraries are currently involved, visit: http://books.google.com/googlebooks/library.html.