I suspect that if an anarchistan would be created within a lifetime it would 'revert' to some other well known political framework, either a democracy or a dictatorship.
If there was an anarchistan in recent history it was a probably Somalia and even there you now find a regular government.
A more appropriate example of "anarchistan" would probably be Catalonia during the civil war in the 1930s. It has been written and discussed by Orwell, Bookchin and many others. Your point is well taken though, at the end it did function as part of a "regular" democratic government before being crushed in the civil war both by Soviet backed communists and Franco.
If there was an anarchistan in recent history it was a probably Somalia and even there you now find a regular government.