How Do I Find Free Addresses and Unused Address Labels?

Free addresses and addresses used without a label can be found in the View menu / Cross-Reference Report button.

There are several options.
For example, if you choose "Usage with comments including unused" , you'll have the following schedule.

Free Addresses

In the table it shows, for each address, whether the data has been used as an address, the contact and the output of the address and how often it occurs in the program. The term 'symbol' refers to whether the address has a name or not. In this example an unused address is 91.02, 91.01 is programmed with some output but has no label.