The AP Physics C: Mechanics exam page from College Board has practice exams and all the released free response questions from previous years.

Review Videos From Flipping Physics and his corresponding review lecture notes.

Review Lectures from Yau-Jong Twu

• Kinematics
• Simple Harmonic Motion
• Rotation
• Her YouTube Channel with videos separated into playlists by topic

From APlusPhysics:

• Review Lectures from APlusPhysics
• Tutorials and Guide Sheets

Practice questions from LearnAPPhysics

• Kinematics
• Newton’s Laws
• Work, Power and Energy
• Impulse and Momentum
• Rotational Motion, Torque, Moments of Inertia
• Oscillatory Motion
• Gravitation

Review Questions with Answers from CrashWhite:

• Vectors and 2D Motion
• Laws of Motion and Circular Motion
• Work, Energy and Conservation of Energy
• Momentum
• Rotation and Angular Momentum
• Static Equilibrium, Oscillations and Gravitation