I've read it over at two sites now, and am still a little unsure:
So, is it true that the Order too had spies within the ranks of the Death Eaters? Is this information canon? If yes, where was this it given?
Setting Off Fireworks in Potions Class
There's at least one spy we know of, and that's Severus Snape. Other than that, I don't think there are any named spies. I suppose you can include Remus as well, since he was a spy amongst werewolves, but that's not on the same level as actual Death Eaters.
Originally Posted by Padfoot Patronus
Tim the Enchanter