Here is an article about the landscape of minor league baseball (independent and affiliated) in New Jersey. It cites population density and number of minor league teams per square mile along with several other factors about the business of baseball in New Jersey:
It has several quotes from executives in minor league baseball including independent baseball executives Frank Boulton, Miles Wolff, and Marvin Goldklang.
There are several good books about the independent professional baseball leagues. You are welcome to see a list of suggestions through this link: Books Get notified of upcoming independent baseball tryouts from either of these services: first service or the second service. Prospective players can find some helpful resources here We will be providing a growing list of possibly helpful tips and suggestions on various baseball information. This will range from "how to" information about baseball skills all the way to helpful information for casual baseball fans. Please click the link for more information: Tips And How To Information