You'd likely have to hire someone to develop a script for you; no tool, that I'm aware of, exists to prune or change permissions on user accounts based on a list of addresses.
A tool would have to be created which would take a list of addresses (likely from a textarea field) and process each entry against your database for the action you'd want (which would likely be either to purge the user, add the user to a specific group so you can process manually, or simply disable their preference to receive admin emails).
