I've actually seen books with ads before, it is not a new concept. Those were rather old books, too (pre-internet). Only very few ads, though, maybe three pages in the whole book.
I like your idea with the out of print books!
I like your idea with the out of print books!
Anyway, reading a book requires a completely different mindset from reading a magazine/ watching TV/ browsing the web. So I guess that's why ads "work" in one medium and not the other.