The Community of Disc Golfers and About All Things Disc Golf
The first thing you need to do to get a rating is join the PDGA. You can do so at http://www.pdga.com/join. In order to get points and a rating you need to play in santioned events. Your scores will be rated compared to the other players that participate in the event. You can see what events in your area are sanctioned by searching here http://www.pdga.com/tour-schedule. I hope to see you out there on the links sometime.
I am old to disc golf and absolutely love it (of course)...
They way to find out how you stack up is to jump headfirst into tournaments. Win or lose, the process is compelling.