For The Raiser's Edge versions 7.91 and below:
  1. Modify the duplicate criteria for the first and last name
  2. Run the Duplicate Constituents Report and mark the Create output query of duplicate records checkbox.
  3. Create a constituent export and select the query created in step
  4. Export All addresses for the constituent's.

For The Raiser's Edge version 7.93 and higher:
Use the Duplicate Constituent Management Tool to find duplicate constituents.