<we found some interesting little potential sites in woods near Fernworthy>

You say in woods near Fernworthy, do you mean in the Fernworthy forest? If so there are a number of round houses dotted around in the forest most plotted out in Jeremy Butler's excellent series of books "Dartmoor Atlas Of Antiquities" volume two covering the north moor. If you know what part of the forest you were in ,and could get hold of a copy, you could check it out. I do not know of any rows or standing stones in the area, other than the ones posted here, but things are still being found. Most of that area was checked by the late Victorian antiquarians long before the forest was planted, but you may have been lucky.

Peace Lubin.