Wait, wait, wait... no true villages? None?

What was the largest concentration of population we've found in this period/area?

Was everyone a farmer? No fishermen, no fishing villages?

According to Islendingabok, Norway was overpopulated. That doesn't neccesarily mean towns or villages, maybe it meant arable land. Only the eldest son inherited land by tradition.

In the period we're talking about, the biggest concentration of population in Iceland would probably have been around chieftains who would have kept maybe 10-30 slaves/servants and an extended family. That makes a grand total of maybe 50. It's a guess on my part, but it's the feeling I get from reading the sagas and looking at photos from excavations (and re-building) of [Stöng] (http://www.thjodveldisbaer.is/en/buildings/fyrirmyndin---stong/) fx.

So how does that translate to Scandinavia? There are certainly richer chieftains there and a king or two so I assume you would find larger concentration of habitation there. Remember that Iceland was only settled in 874 and is 5x the size of Denmark. There would have been no obvious incentive to concentrate habitation. Your incentive would be to stake claim to as much land as you could (and there were rules for that).