Not yet. There is Netflix for XBMC but not for the Xbox version. You have to find a way to get XBMC Eden on your Xbox (Not Original XBMC) The best you can do for now is use the IceFilms plugin for XBMC. And XBMC can be found at the link below.
The reason why is because you need internet access for Netflix. You cannot get internet without Xbox Live. This is why you cannot access Netflix without internet. Also the gold membership for Xbox is $50.00 for a year. You also need a wireless adapter to connect internet to your Xbox.