"libertarian" philosophy 101, at least as its usually put forth, relies on the axiom that initiating force(violence of some sort-physical force), is wrong. It remains wrong if a group of people get together in colorful costumes and call it "law".
MANY "libertarians" -usually called "left-libertarians", don't believe in private property-particularly land- as its currently understood either...since it involves an initiation of force(to their view at least...and I have trouble arguing against it, frankly).
Myself, I don't even use the term libertarian. That said, if you really are interested, and not trolling, most of what you've read above in this thread is derived from Murray Rothbard's theorizing. I'd suggest giving him a read, virtually everything he ever wrote is available online for free http://mises.org/literature.aspx?action=author&ID=299 Here. You are always better off going to the source. But always remember the use of force when reading everyone Rothbard is not perfect on this, even, IMHO.
Not all libertarians hold the view that the non aggression principle is axiomatic.
Then do please provide us with your philosophy-one that does not impose on others, that you like to use the term "libertarian"to describe. David D. Friedman presents one I respect-do you agree with his consequentialism?
As I said, I don't use the term, but academically, "libertarian" means the philosophy of non-aggression. I mentioned that "as i understand it" was my definition to someone who likely is now utterly lost. And since aggression=the state, libertarianism in its true form is anti-statism, or more clearly, anarchism. That was its initial definition.
But the word today means whatever the teller tells you. And this is good-seek your own definition.