What is the top mailing list app for postal address updates and duplicate removal?

[kenetrekjim]

We still mail some printed catalogs and we are looking for the best mailing list application that will allow the export of customer mailing lists for postal address standardization and National Change of Address updates, then the updating of the customer file and removal of duplicates.  What is the best recommended application to accomplish these updates?

We usually update annually and work the data using Access.