"Concept of ruler in Tolkien's works" I need some help ;)

[sphinx123]

Hello
I'm from Poland and next month I'm going to take an exam, actually I need to do a presentation about concept of ruler in Tolkien's works. I'm planning to talk about Aragorn, Theoden, Denethor, Galadriel, Saruman and Sauron. I've been searching in libraries, but they don't have anything useful besides trilogy, Hobbit and Silmallirion. My teacher said, that so far I didn't contained enough professional theories. I think she thought about literature themes, comparisions to other popular books. Aragorn is the easiest character to elaborate, because I plan to compare Narsil to Excalibur and wander of Aragorn to wander of Odysseus. Saruman is wise elder, who unfortunately get corrupted by desire of power, quite clear figure to describe. Could you help me?

[heliona]

You might be better re-posting this in the Books forum, as hardly anyone looks in here any more. I'm sure if you did you'd get an informative response.