The one point I will make is that, when people imagine anarchy, they imagine the society we have now, and then just take away government and all its functions, such as police. Of course what you get when you imagine that is terrible. But it's terrible not because anarchy is terrible, but because our society has evolved for centuries to (a) assume that government will always be there, and (b) gradually put more and more functions on government, even if they would actually be better done privately.
Of course what you get if you take a society like that and just remove government will be bad; but that's not a fair picture of what a society that had evolved for a long time as an anarchy--i.e., in which people understood that there was no government to "fix" all their problems, so they need to come up with workable solutions themselves--would look like. Friedman's book is an attempt to imagine that, in detail.
> we have a lot of evidence of what happens in societies with out 3rd party enforcement
No, we don't. We have a few failed states like Somalia today, but they are few; almost all societies on the planet today have governments.
However, when you start looking back at historical examples, you find much more promising cases. One that Friedman discusses in his book is saga period Iceland, which did quite well for centuries with no government. Other examples are some of the American colonies--Pennsylvania up until the 1750s or so is a good case--which, while they had entities they called governments, used them for nothing except to represent them in negotiations with other colonies and with the British government. These "governments" had no law enforcement powers and no powers of taxation, and people came up with various private means of working together and enforcing what we would call "laws" (but which were not brought into being by legislative fiat, but by contractual agreements between individuals).