The sweet spot and Par train are my go to.
If you love the mental side, strategy based thoughts, nothing on the actual swing mechanics, and great interviews they are both great.
Looking for:
Vokey 3 wedge set: 50-54-58 or 52-56-60 in good/great condition. SM7 or SM8
Also:
JPX 919 tour, lower irons 7 or 8 - PW. Ideally with x100 shafts, but will to buy just heads too.