Last summer we went to the Library of Congress in D.C. I didn't know what to expect, but I really enjoyed it. Duh, me, books, written word, history of writing in America, kind of makes sense! In addition, I found some really great art in the gift shop. We just painted the upstairs hallway, and I've slated these three prints for one of the walls. I think they were from series of postcards or posters, not sure on the history.
They have some really fantastic prints in their online shop, complete with descriptions and back story. These were some of my favorites.