Get any book, most of it is all hype. Eat a healthy diet and you'll be fine. Most herbal cures don't work, anyway. Or they offer some very minor benefit.

Some herbalists who I follow.

https://youtu.be/VFV0tWVSRXM?is=Ueze55NnMV8pw1T-

https://youtu.be/KfIEEvC3zV0?is=4OmLVTv5gAtkqzJM

https://youtu.be/XenNTHa33vY?is=i2q_bsBsj6LArYeJ

Look for books by Dr. Varro Tyler. He was dean of the school of pharmacology at Purdue University, and was renowned world wide as an authority on herbs. He did write a few books but I don't remember the titles.

Most herbal cures don't work, anyway. Or they offer some very minor benefit.

Well, that's just not true!! Herbs and plants (and naturally occurring fungal organisms) are the basis for many modern medicines and have been used for centuries. You can easily find lists online of plants and herbs that address specific ailments, increase energy and brain focus, relieve joint issues and generally improve the state of one's health. Not at all what are considered "minor" benefits. There is even a name give specifically to these botanical products - phytomedicine.

As to books, there are lots that would be useful. Google 'herbal' or 'botanical remedies'. Or 'phytomedicine'. And John Hopkins University and MedlinePlus have detailed websites addressing these products and their use.

Rather than igoring or disregarding these botanicals like the previous poster suggested, the more you know about them, the more effective they will be and with the least amount of risk if creating potions of your own.

If you actually look for scientific studies supporting herbal remedies, the results are underwhelming to say the least. Effective herbal remedies become medicine. Herbs, for example, can vary tremendously in how much of a given effective chemical they have, depending on the soil, the rainfall, the sun, the particular genetics of the individual plant. There's a reason no one drinks willow bark tea for headaches, but people take aspirin --- derived from willow bark.

Google Encyclopedia of herbs or Encyclopedia of herbal medicine etc to get started on finding what you like.

There's a reason no one drinks willow bark tea for headaches

Is there?? Wow!! And yet another big assumption without any substance. I have two members of my family that are serious advocates of naturopathic medicine and herbal supplements. They choose to keep the big pharma middlemen out of their lives. They don't grow all the herbs and plants they consume for health purposes but can obtain the raw materials they may need from local natural food stores, herbal shops and farmer's markets.

It is a big industry! Apparently a lot of "no ones" out there :-)) "The global herbal supplements industry is a booming, multibillion-dollar market driven by rising consumer health consciousness and a growing preference for plant-based, preventive healthcare. Valued in the tens of billions, the market continues to expand as consumers seek clean-label alternatives for holistic wellness."

Dr Tieraona Low Dog, MD and a member of the Comanche nation is a nationally recognized expert on herbalism. Below is from her website:

Tieraona Low Dog, MD, is a physician, educator, thought leader, researcher, naturalist, mother, and wife. She has directed three postdoctoral Fellowships, received a Presidential appointment under Bill Clinton, named Time Magazine’s Innovator in Complementary and Alternative Medicine, is the recipient of four lifetime achievement awards, named as one of the 30 most influential people in the natural products industry, has consulted with many Fortune 500 companies, designed top selling dietary supplements, written four books with the National Geographic, 50+ peer-reviewed articles, 25 chapters for medical textbooks, and spoken at 600 conferences globally.