check the very good articles on Ray trace on fx guide given by Arnold render......

http://www.fxguide.com/featured/the-art-of-rendering/

hi,
      I have started research on Arnold render on maya. u can under stand that its very difficult to get the plugin so  i have asked from my boss to get a new licences for doing RND in this render. this is my starting day. i came to know lot of thing about this render engine. see lot of movie with very good quality render. since i am great lover of ray-trace rendering system. i will keep things updating......in my blog..............