The Buck sounds interesting. Have to get it!
I'm sorry Truman's :library of Congress one wasn't good. I've read a lot of hers, but not that onw.
I love the library of Congress! when I was in graduate school, I did research there, even had my own shelf. I used to wander around in the stacks (forbidden, but that never stopped me: I discovered if you looked like you knew where you were going, no one questioned you. You can't believe what is back there, even little coffee shops. I burned myself on some coffee once, and was rushed through laborinthine passages to an infirmary, complete with all mod cons.
In odd corners, you would find scholar's desks, piled with books (I didn't rate a desk, only a shelf -- sigh). Sometimes the books would be covered with dust, I imagine the scholar had passed away, and his books were waiting for them forever.