Where can I watch planes? (Northern NJ)

However, TEB is closer. At
TEB, I was told by a guard that there is no place on airport property that
I can go, that it's against the law. The only place I have received
permission to watch is a bit far away, and the view is not that great

Havent been there in years but you used to be able to park on the east side
of the
airport on the road to the control tower (off the main road, Rt1/9?) and watch
take-offs and landings there. And it's behind the fence not on airport
property. Of course they might be busting balls for loitering a little more in
our post 9/11 world.
I live 20 minutes or less from Republic here on Long Island and there area
numerous
vantage points to watch ALL types of aircraft from corporate jets, general
aviation,helicopters and even warbirds. They have a nice area to park and
watch by the tower but there are many other places to watch depending on what
runways they are using. And no hassling either.