This will show you in pictures how you may get a list of donors who have not given for any given date span. This will not work in most Contributions reports, but will work for the Master Donor List. It will also work for any people reports.
Print the report. You should get a list of people who are in your database who have not given.
You may also filter for Relation to Church = Member and or ID <= .02 so you only get members who are adults.