1. Navigate to Lists > Manage Lists
  2. Click the Manage basic and advanced lists block under List Actions.
  3. Select Add > Create Advanced List
  4. In the Select Objects tab, on the left, expand Constituent Information.
  5. Select User Base.
  6. In the Select Objects tab, on the left, expand Custom Field.
  7. Select Custom Field - General.
  8. Select the Display Fields tab, click Select Fields...
  9. Expand User Base.
  10. Select First Name, Last Name.
  11. Expand Custom Field - General.
  12. Select the name of the field.
  13. Select the Filters tab.
  14. Under Global Filters, click the Field drop down box.
  15. Select Custom Field - Name of Custom Field.
  16. In the Condition popup, change "is" to "is not null".
  17. Click Select.
  18. In the Name field, enter a Name for your list.
  19. Click Save.
  20. Click Preview to preview your lists results.