I live 3 miles from Batsto. Actually, Batsto and Atsion connect together. Batsto is the southern part of the pine lands. You drive along the Batsto River north and that will take you to the main road, Quaker Bridge Road, that you access from Atsion. Be warned. Bring a GPS. They are so many trails and they all start to look the same after a while.
Batsto is pretty flat and sandy and not much for mudding but is a nice little drive. If you start in Atsion, take Quaker Bridge Road a few miles until you hit Quaker Bridge. It'a big steel bridge that crosses the Batsto River. After that, follow the trails to the left (north) and you will find plenty of place to go mudding. Stay clear of the Jersey Devil
And like Chinarider said, stop by the visitor's center and talk to them. They are really helpful.