This post is intended for people working in Midtown NYC, who might be looking to move to New Jersey, and want to factor commute times into their location decision.
In my search for housing I've put together a map on Google that lays out all of the different train lines in northeastern New Jersey. This map isn't intended to give you perfect accuracy, rather, it's meant to give you an idea of where to start your search. I filtered my results to give a maximum commute time from the furthest terminal on the line...That maximum commute is 45 minutes to Penn Station, with the idea being that once there, you could be to any of the major banks in under an hour. I cross-referenced Google's train line search with NJ Transit's schedules to confirm the timing. The lines are color-coded to match NJ Transit's coloring scheme:
Purple: Pascack Valley Line
Yellow: Bergen County/Main Line
Salmon: Montclaire-Boonton Line
Green: Morristown Line
Orange: Raritan Valley line
Maroon: Northeast Corridor
Blue: North Jersey Coast Line
When figuring transit times I specified an arrival time of 7:45AM. Note that when using Google's transit service for northeastern NJ, both NJ Transit and Amtrak trains are included. Big difference in price, so if you're planning a commute from anywhere along the Northeast Corridor, be aware that Amtrak trains are significantly more expensive and closer in scheduling to a flight vice a more traditional public transportation method. From Trenton, a monthly Amtrak pass runs about $1,150.
Not listed are Newark Penn Station, Hoboken, and Secaucus Junction. Newark and Secaucus are two of the major transfer stations for lines like the Raritan line, which requires a transfer at Secaucus to get to NYP in some cases. I also left the light rail lines and PATH off the list due to their close proximity; Almost everything on the PATH is inside 45 minutes. it goes without saying that Jersey City and Hoboken, two popular locations in NJ, are about half an hour from most points that you'd be interested in.
For commuters outside this range that would still like to take the train into the city and avoid having to park in Manhattan, I can tell you from experience that Secaucus has a large parking lot. I've never not found parking there. Plan for about an hour if you're parking at Secaucus and your destination is near Times Square/Bryant park.
Hope this helps someone.