I've been compiling a list of
New Jersey climbs
it's getting up to around 50 climbs that people have told me about, or that I've known myself.
To help find them, here's a map of NJ hill regions.

The ones I actually ride the most are Warrenville Rd (also Valley Drive + Hill Hollow as warmups) near Rt 22 around Dunellen and Plainfield and Watchung.

Closer to New York are West Palisades Blvd and Fort Lee Rd -- but I like better the Alpine Approach hill at the north end of the river road (even though it's only around 38th in ranking of steepness of NJ hills).

Way out west, Fiddlers Elbow is notorious, with lots of other climbs nearby on different sides of the "Montana" hump. But someone just told me about Iron Bridge Rd and Ludlow Station Rd way out in Hunterdon county on the Musconetcong ridge, which look interesting, but I haven't tried yet.

Ken