are there any Princeton/New brunswick NJ lawyers who would take a copyright infringement case on consignment

You took a photograph, emailed it to a newspaper for some reason, and it ended up in the newspaper's file photography collection. You now object to the newspaper offering to selling the photograph as it does others in its collection.

Has the newspaper refused to remove the photograph from its file collection -- or have you not even informed them of their mistake? Are you simply try to extract as much money as you can out of the newspaper or can you articulate some harm that you've suffered due to the newspaper offering to sell your photograph? Have you ever sold copies of your photograph?

It is highly unlikely that an attorney will take your case -- on contingency or if paid by the hour. There are wrongs that warrant a remedy and there are wrongs that don't. Your's don't.