Also, I read that Viking settlers of Greenland (unforested apart from some really small and twisted trees) acquired wood for building ships and houses by taking it from the Canadian coast, so I guess it's very plausible that they would "raid for wood" along Cape Kraken and Sea Dragon Point, or even along the Stony Shore (although the Stony Shore seems somewhat populated).
Also, about their numbers of ships, apparently at least according to Wikipedia (and since a book I read says the same I suppose this is from original sources) the Vikings sailed as many as 700 ships up the Seine to lay siege to Paris in 885. Although wikipedia also says that these 700 ships carried as many as 30 000 men, while Paris was defended by 200 and still managed to defeat the Vikings, so the "700 ships" figure might be an exaggeration. Anyways the point is that the fleets the Vikings historically used seem rather large as well, so maybe the idea of the ironmen having 500 ships isn't as far fetched as one might think at first.
In addition, I made an estimate about the landmass of the Iron Islands based on this map that allows you to measure distances:
https://sites.google...nixgallery/home
I came up with 20 000 square miles (100x200 miles), which would put the isles close to modern Denmark in terms of landmass (well, actually Demark is about 16 500 sq miles). Although even then, if the population of the Isles is say, 0.8 million, it would put the population density to 40/sq mile, which is probably significantly higher than any other region in Westeros. Maybe the culture of taking thralls and salt wives results in overpopulation which leads to all the raiding (the Reader does mention in AFFC that the ironborn need more land)?
Edited by Charerg, 13 March 2013 - 10:45 AM.