One thing that keeps me from even claiming to be a libertarian is that I'm very skeptical that certain types of commons can be protected without government regulation. One example of such a common resource is air. Therefore, at least for the time being, I accept government regulation of the air, and I accept the loss of freedom, the growth of bureaucracy (the EPA), and the cost in taxes and lost productivity associated with it. It's unfortunate that we have to endure so many costs to have clean air, but having clean air is still worth it to me.
However, I think commons should be privatized wherever feasible, and regulation of the remaining commons should be pushed down to as localized level as possible.