Re: What books helped you the most?.
A couple of good reference books on herbs are:
Potter's new cyclopedia of botanical drugs and preparations
The British herbal pharmacopoea
These are not reading books, but reference books when you want to know the actions of herbs.
A book worth reading is:
Calling of an Angel -- The story of Rene Cassie
This can be downloaded over the internet, and is about cancer. When you learn how the herbs work, you understand the treatment better. You also get a picture of how the drug industry is opposed to effective treatments if they can't make money from them.
I found it beneficial to learn from many different sources. One practitioner may have good knowledge in a certain area, and another practitioner may have good knowledge in a different area. Try to pick up the best from all of them.
Some keys:
The thing is to get every aspect in perspective. Diet and lifestyle is most important.
There are other things, for example: Physiotherapy and corrective exercises are beneficial for joint and muscle problems. The Buteyko breathing technique is good for asthma. So to have a good knowledge, you sometimes need to learn in other areas.
Stay within the realm of scientific possibility. Some people say drugs are scientific, and natural methods are not, so they can trow out all scientific reasoning. Even though herbs are not used by doctors these days, it is still good scientific reasoning to use them. Don't use anything outside the realm of scientific possibility. For example, astrology is something I would not use. I say this because there are some good things and some things I would not use in alternate medicine.
Something coming from a living plant, such as a food or herbal medicine, is better than something synthetic, such as a synthetic vitamin. Too much of synthetic substances, such as vitamins, can be harmful.