Here is a Google Map of a few resorts/mountains in the North East region. If you want something added let me know. Also, there is another thread that covers a lot of the New England region here:
http://www.ridemonkey.com/forums/showthread.php?t=198754
and here is the map:
North East MTB Resorts
http://www.ridemonkey.com/forums/showthread.php?t=198754
and here is the map:
North East MTB Resorts