This topic came up several years ago in a writers group to which I belong. If memory serves me (and if the law hasn't changed), most print material, when purchased becomes the property (the physical book, not the rights to the content therein) of the book owner. As owner of the physical book, you have the right to give and loan. However, selling is a different issue bacause, again, in selling the physical book you are also selling the copyright protected content. There are certain provisions for such sell, however, I don't recall what they were (this was more than a decade ago).
I was told recently by our PR lady it was legal to resell print books. I posed the question when a group of our authors for pirate copies of their e-books on a esnip page. I wondered if places like 1/2 price books and goodwill were breaking a law by reselling paperbacks. I was told no, because the book was already bought. But e-books can be duplicated and are everytime you "share" one. so esintially it is like going into a book store, buying one copy and stealing a dozen. I just wanted to know what others thought about buying used books. Thank you