On June 11, 2018, the FAA updated the Practical Test Standards for the Private Pilot Airplane certificate, Instrument-Airplane rating, Commercial Pilot and Remote Pilot. They can be downloaded from the following URL’s as PDF’s:
Private Pilot – Airplane Airman Certification Standards (FAA-S-ACS-6B, Change 1)
Instrument Rating Airman Certification Standards (FAA-S-ACS-8B, Change 1)
Commercial Pilot — Airplane Airman Certification Standards (FAA-S-ACS-7A)
Remote Pilot – Small Unmanned Aircraft Systems Airman Certification Standards (FAA-S-ACS-10A)
If you would prefer a print book, they can be purchased from Pilot Mall.