Former New Jersian here, if you are looking for Ninjutsu/Bujinkan system the Musan Dojo in Rutherford NJ is an option. It is not to far from the Jets/Giants stadium. A little farther north than you may be looking. Here is a list of NJ dojos form Ninjutsu.com
Jack Hoban Shihan (recommended)
Red Bank YMCA, teaches Mon & Wed.
Living values.com or call for info.
Bujinkan Happo dojo
seniorteacher: Don Houle rankdan: 5
address: 108 Sparta Ave Stanhope, NJ 07860
traininginfo: Thursdays 7pm - 9pm Saturdays noon - 2pm
The Musan Dojo, Inc. - Robert Carcano
P. O. Box 59; 425 Paterson Avenue; East Rutherford, NJ 07073
Phone: (201) 804-0352 or e-mail: firstname.lastname@example.org
Tanuki Bujinkan Dojo
seniorteacher: Shidoshi Christopher Carbonaro rankdan: 7
address: Highlands, New Jersey
traininginfo: Saturday's 10am-1pm
Monday night classes are held at the Spartan School of Self Defense 7pm-9pm
phone: 1 570 977 3596
I trained at Musan a long time ago when I lived in NJ.