There's several ares to launch from in Barnegat Bay to get access to Barnegat Inlet. In the town of Barnegat there is a municipal ramp to launch from and the ride across the bay is about 4 to 5 miles to the inlet.
You can also launch in Forked River. Coming north on the Garden State Parkway get off at the Forked River exit and turn right at the end of the ramp. THis should put you onto Lacey Road. Take that into Forked River and cross US Highway 9. About 1/2 t 1 mile down on your right there is a marina (used to be called Townsend's, but I hear it's been sold and may be under a new name) that you can launch at. You are now in the Forked River (after launching). Just follow it out to the bay and the trip across is about 5 miles or so to the inlet.
There used to be good fishing just on the north side of the inlet in the flats area of Island Beach State Park. Also, on the way out the inlet the rock jetties used to hold some nice stripers. Used to plug them with a Rappala or a Rebel lure, but I'd bet that a jig and a grub would work real well in there.