Newsfinder is a utility application that helps you find free news servers.
It does this by starting with a server that you have access to, and using it to see what servers other people are posting from.
It then checks these servers by trying to log in without authentication and finds out if it can be done successfully.
Unfortunately, public news servers are exceedingly rare these days, and you probably won't have much luck finding one.
But, you're still welcome to give it a shot. The software is free.
If you are unable to find a good 'free' news server, then there are lots of excellent pay news servers. Many offer inexpensive plans depending on what your monthly bandwidth requirements are.