If you are interested in Libertarianism but you instinctively are suspicious of capitalism or even currency, perhaps you would be interested in Anarchism. You can read about many interesting aspects of Anarchism with regards to its relationship to other ideas such as Capitalism, Marxism, State Socialism, and the current system we have in America.
http://www.infoshop.org/faq/index.html
If you think the abolition of money and markets is the abolition of economies, you are wrong and I invite you to read this very short intro to Anarcho-Communism, a post-capitalism way to live and organize.
http://struggle.ws/wsm/rbr/rbr10/communism.html