As mentioned in my post The Best Introduction to Libertarianism Ever, attorney and legal scholar Jacob Huebert has written a fantastic introduction to the modern libertarian movement. His chapter “The Fight against Intellectual Property” is also one of the best, most concise presentations of the libertarian case against IP I’ve ever read.
It’s no surprise, then, that Huebert’s performance in a recent IP debate at Whittier Law School is superb–this is just a great presentation (audio). His opponent gave it a good shot but really had no coherent argument to mount in favor of IP at all. It just goes to show you, there are no good argument for IP; this is why pro-IP libertarianism is on its death bed.
(See also Huebert’s wonderful recent Mises Circle talk, “Is There Hope for Liberty in Our Lifetime?”.)