Passed by Congress and signed by President John Adams in 1800, the Library of Congress Act provided a reference library for Congressional use only, containing "such books as may be necessary for the use of Congress - and for putting up a suitable apartment for containing them therein...."
Allowing $5,000 for the plan, the original library was housed in the new Capitol until August 1814 when British troops set fire to the Capitol Building, using some of the books and materials of the Library to start the blaze. The next year the United States Congress accepted a longstanding offer and bought 6,500 books from Thomas Jefferson to begin a new library.
Today, the Library of Congress houses more than 130 million items including nearly 30 million books and other printed materials, 2.7 million recordings, 12 million photographs, 4.8 million maps, and 58 million manuscripts. This is all stored on some 530 miles of bookshelves. The Library of Congress employs a staff of more than 6,ooo.
The Library of Congress has an interesting web site which includes capabilities to search their vast catalogs. You'll find that home page right here.