I think Proudhon may be getting a bit outdated, in the same way that some really really old dude's rants against kings and monarchs isn't really relevant to our present economic situation. Sure, there are still a lot of old capitalists who own their vast wealth thanks to force, that there are more and more new capitalists that earned it through just capitalism. Examples of such capitalist ventures that are the new super-wealthy that didn't use force are Facebook, Apple, Amazon, and even Microsoft and WalMart. All their wealth came from innovation, and people wanting to give them money in exchange for their products.
By the way, Chomsky's anarchists don't sound all that different from anarcho-capitalists. It all only depends on whether those organic units/communities would freely give up all their belongings freely to any passerby who asks for them, or whether they should protect them and give them up to other communities in trade.
Sorry Rassah, but you lack fundamental knowledge on the matter (no offense intended). In anarchist philosophy there's no "giving all your belonging freely to any passerby", that's charity, which is a christian concept abhorred by anarchists.
First, one thing is personal property (your clothes; your furniture; etc.) and a very different thing is private property (which refers
only to the means of production: the land; the factory; etc.).
Secondly, most forms of anarchism are not against the existence of free market (except for anarcho-communism), they are against
capitalist free market.
Thirdly, anarcho-chapitalist don't accept state hierarchy but accept private hierarchy as the natural state of things. I'll put it silly simple: an anti capitalist anarchist would never accept to be a boss, nor to have a boss. For a collectivist anarchist self-control of the proceeds of his work is fundamental for his liberation as an individual. In collectivist anarchism the workers themselves would decide what to produce, how to produce it, and wether to trade those proceeds or not. For an anarcho-capitalist it's ok to rent his labour at market price (something that for a collectivist anarchist would mean "voluntary slavery"), as long as that its the most
profitable option for him. It's basically a very different philosophical approach on what freedom means, and which do you think is the
natural way to manage your own time and work.
I'l quote again Chomsky just because, while it can be criticized in many things, he is incredibly clear in his exposition, and he is a character with which US folks should be familiarized with:
"Now a federated, decentralized system of free associations, incorporating economic as well as other social institutions, would be what I refer to as anarcho-syndicalism; and it seems to me that this is the appropriate form of social organization for an advanced technological society in which human beings do not have to be forced into the position of tools, of cogs in the machine. There is no longer any social necessity for human beings to be treated as mechanical elements in the productive process; that can be overcome and we must overcome it to be a society of freedom and free association, in which the creative urge that I consider intrinsic to human nature will in fact be able to realize itself in whatever way it will."
Chomsky is quite the prototypical marxist, thus he thinks that capitalism
alienates that creative urge intrinsic to human nature he mentions above. Anarchists and other marxist influenced thinkers believe that labour is a fundamental aspect of individual freedom, and this aspect shapes society as a whole. For a marxist, a worker developing his labour in a privately owned system is alienated from his own humanity, becoming a tool for others.
In a nutshell Marx's Theory of Alienation is the contention that under capitalist conditions workers will inevitably lose control of their lives by losing control over their work.
This "theory of alienation" is one of the cardinal points of The Capital, and Marx thoroughly describes 4 differents types of
alienation that happen in a capitalist society (
https://en.wikipedia.org/wiki/Marx's_theory_of_alienation#Types_of_alienation). Understanding those points is crucial to understand past and modern critics to the capitalist system.
BTW, if you'd like to have a "soft and easy", "american" and modern first approach to collectivist anarchism you could start with this:
http://www.amazon.com/Chomsky-Anarchism-Noam/dp/1458787435.