I thinking of arwen's riding costume when she goes to the ford, it is meant to be light! I tried to get a picture but got a sight look at it
http://www.shadowdalecreations.com/lordoftherings.htmOr something a bit more boyish, but just do type in the search engine female warrior costume (groan), if you want to fight i was thinking of what elizabeth wore in pirates of the Caribbean films, not the dresses but the lose shirts and army jackets, trousers with a belt around the middle?