I think most of the ebooks that sell the secrets to growing taller are all fake scams. There are no secrets in the medical world. Stretching exercises can work but don't exactly make you grow because to grow you need cellular growth which stop after a certain ages as your growth plates fuse together.
Stretching exercises instead will stretch out the space between joints and vertebrae in the spine making the gap between the bones bigger and the stretches will help to also strengthen the surrounding muscle around the bones and spine meaning this gap doesn't become compressed together again by gravity... i think that why spacemen are taller in space and people are taller in morning as gravity has compressed them together either yet.
Diet will only work whilst your still growing of what iv heard. As you need essential amino acids found in foods rich in protein to promote growth and repair in the cells also you need strong bones for growth so calcium and phosphorus is needed. But to properly absorb these minerals from your food and milk you need sunlight (vitamin D)... A BALANCED DIET THEREFORE IS ESSENTIAL WHILST YOUR GROWING.
Height increasing insoles have been used by some to get taller as well. For those who have stopped growing and have not got time to do stretches...or for those who have done the above methods and want even more height. The shoe lifts work instantly and are adjusted too so you pick what height you want.
Well that's all i know about growing taller anyway hoped that helped