Family Search has recently updated its database, New Jersey Probate Records, 1678-1980. Currently, this database is not indexed online and does not have a search feature. However, you can browse through the images which are broken down by County, and then by record type (see Monmouth County records, for example). My suggestion is to use the images in conjunction with the published series, Index of Wills, Inventories, Etc., In the Office of the Secretary of State, Prior to 1901, which are available online through Google Books.
New Jersey Index to Wills, Inventories, Etc. v.1 (Atlantic, Bergen, Burlington, Camden, Cumberland, Essex Counties)
New Jersey Index to Wills, Inventories, Etc. v.2 (Gloucester, Hudson, Hunterdon, Mercer, Middlesex, Monmouth Counties)
New Jersey Index to Wills, Inventories, Etc. v.3 (Morris, Ocean, Passaic, Salem, Somerset, Sussex, Warren Counties)
The information found in the published indexes (arranged by county and then surname) will allow you to narrow down the search to the county and the type of document, and will give you the document's file number. With this information you can now maneuver through the appropriate image screen in the Family Search database until you find the file you are looking for.
For example. In volume 2 of the New Jersey Index to Wills, Inventories, Etc., I went to the section for Monmouth County, and looked up Daniel Bennet (he is found on page 922). From the New Jersey Probate Records Counties Page, I select Monmouth County, which brings up the links to the various films that have been digitized. The entry for Daniel Bennet in the Index tells me to search for File 11183 M, which includes his will (signified by the W), dated 1850. In the list of links for Monmouth County I scroll down until I find Wills 1695-1900 no. 11100-11220 (which would include no. 11183 M). Daniel Bennet's file, no. 11183 M, begins at image 652. Finding this image was a matter of strategically working through the image numbers until I closed in on file no. 11183 M. It took me about five minutes to find the correct image. With a little luck it could happen faster, but it still beats ordering the film from the Family History Library, waiting a few weeks or more to be delivered to your local center, and then taking the time to visit the center to view the film. And you can download and save the images you need.