The Unpaid Employees Report lets you see details of employees (non-terminated) that have not been paid since a particular date.
This report can be found by going into the 'Reports' homepage, and finding it under the 'Employee' heading
When you are in the report screen you can specify the information by date (since last unpaid), pay schedule (see here for help on pay schedules), and employee locations (see here for help on locations).
The results will then show each location and list the employee along with their employment type and the date that they were last paid.
This report can be exported as an Excel, CSV, or PDF file.