Here are some links that you may find helpful while browsing the SLD webpages Maps of New Jersey Counties - This webpage will give you a map of all of the counties within New Jersey.
There are also links to full maps of each county if you want a closer look at a specific one. In the county maps you can find sidewalks, bike lanes, highways and more. You can also download and save PDFs of each county map.
This website also has GIS data for each county linked for download.
NJDOT Roadway Design Manual - This document has a lot of information on elements of roadways and different attributes.
NJDOT - The official web site for New Jersey Department of Transportation
Social Media - NJDOT Facebook - If you are looking for quick updates through social media