Amtrak Northeast Regional operates a train from New York to Stockton hourly. Tickets cost $70 - $190 and the journey takes 55 min. Alternatively, Trans-bridge Lines operates a bus from New York to Stockton 4 times a day. Tickets cost $25 - $45 and the journey takes 1 h 59 min.
From New York Penn Station train to Trenton Transit Center Amtrak then taxi to Stockton. 1 h 23 min $194. From New York bus to Lambertville, New Jersey then taxi to Stockton. 2 h 5 min $61. From New York drive to Stockton. 1 h 22 min $8.