Hello there, cjnix27.
Right now, printing the mailing labels from the customer list is unavailable. Though, you can run the Customer Contact List report and export it to Excel.
Here are the steps:
Once exported, you can use the mail merge template in MS Word to create a mailing list.
I've got this article for the step by step instructions: Create a Mailing List Using the Contact List Report.
You can also check any third-party applications in the App Center by following these steps:
If you have other questions or concerns about QuickBooks, please reach out to me. Thanks.