The Public Library is a wonderful refutation of libertarianism. In a libertarian society commoners wouldn't be able to read, much less access books for free.
1. The first public libraries were created by charity, not government per se. Andrew Carnegie used his own money, and the money of other capitalist tycoons, to found many libraries.
2. Books aren't expensive. A book would cost your average worker no more then an hour's pay, usually less. And used books are cheaper - At privately-owned stores, I've seen old paperbacks for $2.
Libraries were around in the United States for over a hundred years before Carnegie started his. They date back to Ben Franklin's day. And I hope we never reach a point where libraries exist only at the will of the rich. Carnegie, if he did as you say, did a noble thing, but not all rich people would be so inclined.
I like libertarians but as a librarian worker myself I can't call myself evil.
Most new hard cover books are $15-25, so that would cost 1-2 hours of work, using the average hourly wage in the U.S. right now which is either $13 or $15 (I forget). But the primary purpose of books should never be money. They are essential to a free society, don't make me go into my Patriot Act/Library spiel