Looking for medicinal herbs for garden i.e. curcumin - can't find where to buy organic seeds/and or rhizomes for these.

There are many places - a Google search turned up over 20. For example:

Park Seed: Seeds for Vegetables and Flowers plus Seed-Starting Supplies and Bio Dome!

http://attra.ncat.org/attra-pub/altseed_search.php

Kitchen Gardeners International

http://www.groworganic.com

Organic seeds, Heirloom seeds, un-treated seeds, seed suppliers

Organic Heirloom Seeds Tobacco Peppers Herbs Tropicals Pest Eden EONS URL www.eonseed.com

Territorial Seed - Vegetable and Flower Seeds @ Territorial Seed Company


Also check your local nursery - they have resources for natural/organic plants and herbs.

Good luck!

Here is an excellent nursery specializing in medicinal plants. A quite extensive selection:

Medicinal Herbs & Herb Plants Nursery - Healing Herb Plants