How can I moderate new user registrations?

I don't want users to be automatically added and gain access to the site as I will not be using a payment gateway at this time. As a sports club I want to approve access if they have paid their dues to me and dues to other governing bodies.

If that is not easy to do I do not want a registration page to be available / visible at all so that I will manually add the members. We are small so this would not be a problem as an alternative.

Many thanks,
Stephen