I've put together a number of interesting You Tube videos I have been watching about recovery gear below, including snatch straps, ropes, why not to use a tow ball, and shackles.
Dangers of Snatch Strap Recoveries - Destruction Testing
Recovery Rope vs Strap - Matt's Off Road Recovery and MadMatt's experiences
A Tow Ball is NOT an option in a 4x4 Recovery? FIND OUT WHAT GOES WRONG
4x4 Soft Shackles vs Bow (Steel) Shackles