Some extreme Libertarians think governments have an extremely limited place - protecting personel and property rights, for example. Others are outright anarchists.
Though there's a number of different kinds of anarchists, who really don't agree with each other - the "Anarchism" page on wikipedia is both "part of a series on Libertarianism", and "part of a series on Libertarian Socialism".
So when I said "there's two types", I was lying a bit.
[Note I'm not being snarky: where I am, I've never heard anyone describe themself as a libertarian but I have met people who claim to be anarchists].