"A library outranks any one other thing a community can do to benefit its people. It is a never failing spring in the desert." Andrew Carnegie - see here for photos of the 10 Carnegie Libraries built in Toronto.
This is the Walstrom House by California-based architect, John Lautner. Even though I would not classify this as a library per se, I find the design of the bookshelves in the open area floorplan as a unique twist to a reading space.
Morgan Library, USA Constructed in this amazing New York landmark was originally built as the personal library and museum space for financier Pierpont Morgan’s impressive collection of rare books, manuscripts, drawings, artifacts and prints.