For your Colonial New Jersey ancestors, use the free online
* Abstracts of wills
* Early land records index
You will probably want to use the Dutch Reformed Church records, but I am not as familiar with those.
Many sources for this period are print only and still in copyright. The Genealogical Magazine of New Jersey is a source many are not aware of, but is usually the first place I look. Unfortunately the State Library is closed, but I can do lookups when it reopens.
Sources-New Jersey links the sources above and a few hundred other sources and books; myself and others add to it continually.