There is a UK company, also available in the USA, called WOW! Embossing Powder. You will be amazed at all the colours they have available. Link is
HERE.
I've linked to a search for Brown EP. The quality is really, really good, and I have bought masses of them, with no complaints.
They have loads of other stuff too, like moulds, Heat transfer Foil, even stamps. And some amazing glittery, sparkly powders too.