When you look up on Wikipedia, you'll even find that "libertarianism originated as a form of left-wing politics such as anti-authoritarian and anti-state socialists like anarchists, especially social anarchists, but more generally libertarian communists/Marxists and libertarian socialists."
Another quick search, and you'll find that:
> Right-libertarianism, also known as libertarian capitalism or right-wing libertarianism, is a political philosophy and type of libertarianism that supports capitalist property rights and defends market distribution of natural resources and private property. The term right-libertarianism is used to distinguish this class of views on the nature of property and capital from left-libertarianism, a type of libertarianism that combines self-ownership with an egalitarian approach to natural resources. In contrast to socialist libertarianism, right-libertarianism supports free-market capitalism. Like most forms of libertarianism, it supports civil liberties, especially natural law, negative rights and a major reversal of the modern welfare state.
So I do think it's right to make the distinction between left-wing and right-wing libertarianism.