Well, when it comes to property rights, land will always be the trickiest to figure it out. Rothbard goes into this quite a bit in Man, Economy, and State. Basically, originally land is unowned, and it becomes owned by the act of occupying, possessing, and improving it. Once that ownership is officially recognized in some way, there then becomes a chain of custody with legal deeds and such.
You make your first mistake in claiming that law requires government. It does not. Common law was originally developed by competing courts and jurisdictions. You can still have law with private, competing courts. It won't necessarily be universal law, but if you think we have universal law NOW, you're incredibly naieve.
Your second mistake is considering groups rather than individuals. Voluntarists have no use for collectives like that. Israel right now does not belong to "the Jews" but rather it belongs to the individuals within Israel who happen to own property. Most of them happen to be Jews. If a bunch of Muslims wanted to purchase all the property in Israel until THEY comprised a majority, that would be fine too.
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SmartMuffin - Because anything less would be uncivilized - http://img.imgcake.com/smartmuffin/barkleyjpgde.jpg
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