The first mention Julie Powell makes of libraries is on page 32 (I don't know if there are others, having only read to page 106 so far). She says "...I flipped through the book [Mastering the Art of French Cooking], trying to pronouce all the French words under my breath. An old smell came off the pages, musty but not like library books. More like a dog or a forest floor, something damp and warm and living. The words, and the smell, reminded me of something-but what it was I couldn't at first figure out...."
[several paragraphs follow in which there is a clear connection between sensuality and food]
"It sounded weird. It also sounded kind of well, dirty."
"I suddenly remembered exactly what the book reminded me of."
So, as is my wont, I had this passage marked so I could blog about it, after all, it is about libraries. And then, today, purely by coincedence, my boss sent the following story about why musty books smell like they do.