For some days ago I was searching on youtube for medieval-hairstyles and I found something that I think would make a very good hairstyle for a lady from either Rohan or Gondor (or perhaps only Gondor since it isn't so suitable for riding).
I made a hair-net-ish hairstyle of the hair from the front part of my head. Then I gathered all my hair into a ponytail and made two lace braids which I pinned to the base of the ponytail. Haha, this was literally the most crappy explaination ever so if you're curious how to do this hairstyle watch the following youtube-clip from which I got the idea to make the hairstyle. (Oupsie, it was impossible to insert the actual video clip to my blog, but click here if you want to watch it.)