Stewardship and growing your own is what I suggest to most people looking to use herbs medicinally. This is even more so for the herbs like these that have been overharvested.

The herbs I've grown successfully or unsuccessfully in Western NY:

American Ginseng (Panax quinquefolia) - Not successful. I planted a plant once. Had it for a couple of seasons before it died. Too expensive to try many like that. Seeds planted have not germinated. Love to try some rootlets.

Black Cohosh (Cimicifuga racemosa) - Super easy. Big and beautiful plant.

Bloodroot (Sanguinaria Canadensis) - Expensive to source the corms but easy keeper. Mark well as they and many spring plants are invisible most of the year.

Blue Cohosh (Caulophyllum thalictroides) - Despises the sun. Make sure the spot is full shade, but pretty easy.

Echinacea (Echinacea spp.) - Everybody should have these! Winter sown seed of the various varieties works very well.

Gentian (Gentiana sp) - Unsuccessful. I'm a 3-time looser here and won't try again.

Goldenseal (Hydrastis canadensis) - Very successful in the right place -- until rodents dug up my growing patch. :( Expensive to replace but sometime I will.

Partridge Berry (Mitchella repens) - Limited success. Probably won't try again. I'm a 3 time failure on this.

Spikenard (Aralia racemosa) - Can't kill the one I planted. Gets large - think bush-like. Pick your place well! Super easy!

Trillium (a.k.a. Beth Root) (Trillium erectum) - I've planted a variety of types with limited success - they grow but not vibrantly. I do not think trillium are overly found of my woodland garden.

Turkey Corn (Dicentra canadensis) - very easy. Squirrel corn is a cute plant.

Ginger (Zingiber officinale) - house plant only! But rather fun to keep. Turmeric is even more fun. Can't harvest from house plants - no size.

Wild Yam (Dioscorea villosa) - On my 3rd try with this one. I thought it was dead but last year it sprouted and grew well even though it had been MIA for 2 years. Won't try this one again.

FataMorgana

I have (here in low-country, not up-country Hawaii) a very few, though I have been toying with expanding:
Ginger (all in pots due to inability to find them during dormancy):
Common ginger, zingiber officinale
An eclectic collection of other gingers and turmerics:
Black turmeric, mango ginger (which is actually a turmeric), galangal, finger root (lesser galangal), shampoo gingers, cardamom, etc.
Kava: Unknown type. I assume it is "the Hawaiian kava" as I bought it from a vendor who specializes in indigenous and endemic Hawaiian plants--but you never know.

Well, so I guess I only have maybe two from your list. I am interested in the wild yam and have been considering ordering it.

Thanks for the thread. More people should be interested in these plants. Maybe if people from different zones all grouped together and planted and shared, they wouldn't be so endangered.
--Lee