I had a really good piece of cheesecake at Andy's Corner in Hawthorne. Dense but not too heavy.
The Ridge Diner has excellent cheesecake, and can be ordered small or large, with various toppings.
125 Kinderkamack Road
Park Ridge, NJ
Amy's cheesecake at the Milford Oyster House in Milford is extraordinary (Amy is a co-owner of the restaurant).
The regular cheesecake at the Readington Diner in Whitehouse is very good. Don't go for any of the fruit-topped cheesecakes. I think the fruits are made in a chemical plant just off the turnpike! In season, the pumpkin cheesecake is also delicious.
Niko's Trapezi in Long Branch has killer cheesecake. Had some last night, chocolate marble with chocolate ganache... dayum!!! I've also had the pumpkin and plain, all excellent!
SUBLIME in Gladstone,NJ. Brand new place in the old Opah Grille location. They do a "daily cheesecake" that changes about once a week. All made on the premises by their chef and of the ones I tried, I couldn't possibly tell you which one is best. They've all been out of this world!!!