Here is where I bought the dyes I used today -- at the market in Urubamba, Peru. I only wish I had gotten more, because they work beautifully. I am so happy with the results.
The only strange thing is that my fingernails now look like they have green polish! I used gloves, of course, and my fingers themselves show no discoloration, but my nails have gone from a pale pink polish to green. There weren't any holes in the gloves, either. Weird.