Trekkerj, not sure if you've checked out the NYC Heli feeds but they're a great way to get a feel for the radio calls in the area. Plenty of fixed-wing traffic on them. Coming from MMU you could transition over EWR...just call up EWR Tower on 127.85. You'll most likely be given overhead 22 numbers at 1500 or 2000, then can descend into the exclusion shortly after.
Coming down from the north, you can make your call upon passing Alpine Tower. You likely won't be cleared in for another few miles, but LGA will be aware of you. You could go via NY Approach (may be 120.8 or 126.4 there, not sure) and ask for a handoff but I haven't tried that method yet.