I am thinking of starting to take the plunge with some gear and practice this year and the goal of making some trips next year. There are actually quite a few areas.. Tucks being one of the better known. There is a hilarious video of a girl losing it at Tucks on YouTube.
The EastCoast thread at TGR is a good place to look for some info. Also check out this blog :
Nor'Easter Backcountry: Backcountry Ski Trip Reports
These dudes post a lot and have recommended Mt. Cardigan (NH), Greylock (MA), and The Sherburne Trail (NH) for first time tours.
There is a Lost Ski Area near me in Jersey that is part of the county park system where I have heard people have earned turns before. If we get a winter with enough snow I may give it a look. I know the park decently but not the area that used to be a ski area.
Also might pick up this book.
AMC Best Backcountry Skiing in the Northeast - Appalachian Mountain Club