I can't find the Dryad or Elemental camps :/
I'm not sure about the Elemental camp, but you find out about the Dryad camp from asking around at the yurt, which you discover by asking around at the farm by the lighthouse. The Dryad camp itself is in the forest to the upper right of Castle Corundum and left of the security checkpoint. It's a leafy stalk formation in said forest.