I live in NJ, USA, & I want to start a community newsletter. What are any laws/legal requirements I should know about newsletters?

There are, to my mind, no restrictions on starting a private newsletter. You just have to observe the law when it comes to things like defamation, local obscenity laws, fraudulent advertising, subscriber solicitation, etc. And if you're making any money from it you of course have to report the income on your taxes.

I would take a look here to get some pointers: