This thread is great! My library-science-educated-lovely-girlfriend is going to get that book as a gift, daisy!
When stuck away from home due to a snowstorm (at home, so we couldn't drive back), we were in a small town in Oregon that had a Carnegie Library. The librarian was very nice and happy to tell us about what work had been done, and then undone, to restore it more to the original. What a great way to spend time in a new city - it's like geocaching for library geeks!
You do know, don't you, that one of the options when flying in to NYC is to take an airport bus to Grand Central terminal or the NYC Airporter? This stops only two blocks from Bryant Park, and the lions shown in nukediver's picture. As you walk west towards 5th Avenue along 41st St., you can read the bronze plaques set into the sidewalk with quotes from books, as described in this article about Library Way. I'll often take this way into the city from JFK instead of using the AirTrain+subway, especially for traveling during rush hour while carrying a bag. It's a more pleasant trip into Manhattan, and you can see more of the city going in, while your bag is stored below. It's also air-conditioned, if you're traveling in summertime. I carry my Tri-Star (or, it used to be my Aeronaut by default), and walk up a block to Madison Ave., reading the plaques. The uptown express buses run on Madison Ave., and the downtown express buses run on 5th Ave., with a stop just past the Library Lions.
The only thing to know beforehand, if you're not within walking distance of your destination, is that the buses either take coins (including dollar coins, but not pennies), or MetroCards (with magnetic strips) – no bills. One of the Hudson news stands at the airport (sorry, can't remember which one) still sells MetroCards, I think.
Oh yes.... I worked for NYPL for a number of years and lived in the City for a total of 7, almost 8, absolutely spectacular years. Patience and Fortitude (names of the lions) are friendly faces for me... when it was still possible, I'd often take my lunch to the library steps on the weekend and simply sit, eat, and write while watching and hearing the world go passing by. Fantastic! SIGH...so many great memories of learning what "home" can mean during those years and dear, incredible friends.
Also, If you come into Laguardia, the M60 is a local bus that picks up right outside the terminal doors and will get you into Manhattan--for 2.50. It's a squished ride, but cheap!
I'll just reiterate what Peregrina just stated!