NWS is voting, NWSA is non-voting. NWS generally commands a slight premium. Class A and B are both part of the spinoff AFAIK. I don't think there are SEC filings yet (e.g. 10-12b or 10-12b/a) but check the 8-k's they might have some more info. There was also an announcement of the new corporate hierarchies on the News Corp Investor Relations in December.
I tried posting the news corp link before but yahoo says it's "spam".