This is a list of commonly used resources / guides that will assist in your studying.
FAA Handbooks
Pilot’s Handbook of Aeronautical Knowledge (FAA-H-8083-25B)
Airplane Flying Handbook (FAA-H-8083-3B)
Instrument Flying Handbook
Instrument Procedures Handbook
Weight & Balance Handbook (FAA-H-8083-1B)
Aeronautical Chart User’s Guide (for vfr maps)
Federal Aviation Regulations (FAR)
Aeronautical Information Manual
General
aviation.weather.gov
1800-Flight Service
Student Pilot Guide (Change 1)
Pilot Safety Brochures
Temporary Flight Restriction list
Airworthiness
Airworthiness Directives (AD) and Biweekly listings
Type Certificate Data Sheets (TCDS)
Supplemental Type Certificate (STC) Search
Technical Standard Order (TSO) Search
Aircraft Registration Search
Aircraft Registration Forms
Aircraft Repair Station Search