This is the charter and FAQ for free.
Nothing is forbidden.
This document is an introduction to free. Your best bet is probably to use one of them. You could, of course, ask your news administrators to pick up the hierarchy, which shouldn't be very challenging. If sufficient interest is there, most admins will pick it up, and interest is often determined by user requests. Because this is a FAQ that doesn't want to be updated every couple of days, it's not going to list off the newsgroups in free.