This gesture is super, super romantic movie cute. Real life cute though? I'm not so sure. As a woman, unless I truly felt there was a mutual personality click and physical attraction, I would think this is a bit desperate and possibly creepy. I mean, it's her JOB. Not always the most appropriate place for these kinds of things and I'd be annoyed if it was done at mine.
Either way, I do hope it works out for you though. Life's too short, it's worth a shot. Just end it at the book if you hear nothing else. That HAS to be the end of this or then you truly are a total creeper.
On the flip side, I did something like this before.
I left a sticky note on a womans car who I had a conversation with as I was cleaning my car at the apartment complex we lived at. She texted me, and we dated for a while.
Just do it. If she doesn't call/text back, move on with your life.