Thank you! Is there a central zone for the guild traders?

Every zone has one big city where you can find 6 traders in one spot. All of them could sell Iron, I just mentioned the first 2 zones as it's very likely to find it there.
You can always go back to a zone that you outleveled to harvest crafting materials, they won't disappear. Also in Cyrodiil or Orsinium you'll always find crafting materials that fit to your skill. So if you haven't leveled blacksmithing yet, you'll find iron there aswell.

fetito666 wrote: »

I think I outlevelled the zones and I cannot farm it any longer. *blush*

All zones are static in the raw mats you find, other than Wrothgar and Cyrodiil. So, just go back to the Starter Island or Zone 1 and you can farm Iron Ore all day long. Note, it is one of the harder Ores to see, the others have colors that stick out on the landscape.

I would advise against buying it as raw materials are very expensive. Just take an hour or two an run around your zone mining it. Stick to the base of mountains or other rock formations. You'll find a ton and it's free!