Ginger (Zingiber officinale) usually comes from far, far away, and it is a completely unimportant import crop that is grown in places where something else should be cultivated. So: Ginger from the shop is someone else’s hunger.
But as with all capitalist products, you can find it in abundance in the west – in the rubbish bin. Usually it gets thrown away because it starts to sprout, or “shoot”. Take a medium sized piece (ca 5cm) and put it in a pot, keep as sunny as possible and hydrated, and wait for a while. It’s also a nice bamboo-like, “exotic” room plant. You can use the leaves for herbs tea straight away btw. (In the €uro-zone it will probably not flower but dry out in mid winter)
Turmeric (Curcuma longa) is not so different, it’s even in the Zingiberaceae (Ginger) family: look for some fresh Turmeric root in an organic shops – it’s just cents. (Maybe you can get a sprouting one for free even)
Note: the Turmeric grew slightly better than the Ginger. It’s bright orange inside the peel (bottom left).
I do loooorve rhizom plants – just put some promising bits back into the soil, and repeat.