You need at least three tables for this as this is a classic many to many relationship issue.
other contact Info fields
Any other fields you want to document the specific message--including the actual message if desired
Your relationships would look like this:
People:: PeopleID = People_Correspondance:: PeopleID (Enable allow create and delete options for People_Correspondance)
Correspondance::CorrID = People_Correspondance::CorrID (Enable allow create and delete options for People_Correspondance)
To log who recieves a given correspondance, create the correspondance record and use a portal to People_Correspondance to assign recipients to your distribution list. (Fields from People can be placed in this portal to help make it easier to work with.)
A portal to People_Correspondance placed on a People layout will show which messages were sent to that individual.
To pull up a list of all people who were not sent a particular message, use this layout in a find:
Enter find mode
Enter either the corrID for that message or (If you've put such a field from Correspondance in the portal) the name of the message in a Correspondance title field.
Select the Omit option from the status area.
Perform the find.