I lucked out and found plants at a local nursery and scooped them up fast!
To harvest, strip the leaves from the stalk in fall (BEFORE frost, they can't take ANY frost) and dry the leaves on a screen or net in full sun for about 12 hours. Crush or grind in a coffee grinder. Whala!
For great...
Yes, I grow Stevia in my herb garden. Right now I'm hardening off some to be planted in the ground. I grow it in containers in a sunny window in the winter.
I am a Stevia nut. It's the only sweetener I can use. But the cost is getting prohibitive. :(
I am a Lavender Lover too, and I grow mine in pots with great success. I overwinter the pots on my south facing sun porch. They do great.
Here's a wonderful site:
www.daybreaklavenderfarm.com
I use their soil recipe and its never failed.
HTH