Instantwatcher, a free service that describes itself as helping "you find good streaming titles from Netflix" is updated regularly with new info about the burgeoning streaming films now found on the site of the changing DVD company. There are two levels of membership, though if, like me, you just want to know when new (meaning old and rare for me) stuff appears there, the basic membership seems sufficient. See more here:

http://instantwatcher.com/

 

I found that the feature allowing you to look at available films by the year of release is enough to make me salivate discreetly. You may wish to see more here:

 

http://instantwatcher.com/release_years