The RSVP process is tied in directly with the events section. When you invite people to view your event they are sent an email inviting them to RSVP. They are then taken to a page that looks like:

Once they click RSVP they then see this:

When somebody rsvp's to an event it reflects directly in your admin section. They will show up under the events section tab as well as the activity feed on your dashboard. If you click the little person icon you can view who has rsvp'd.: