The free market exists in every voluntary exchange of private property. It has been, is now, and will continue to be the source of the world’s prosperity.
There are several Economic Freedom Indexes that have established a positive correlation between the extent of economic freedom and measures of prosperity across scores of countries.
http://www.heritage.org/index/default
There have been economies nearly free of state activity: some of the American colonies, some areas of medieval Europe, and so on.
http://mises.org/document/3006/Conceived-in-Liberty
http://mises.org/daily/1121/