Hi wistfuljane -- I meant to reply to your comment, but just realized that I posted my response as a comment of its own, instead of as a "reply" to your comment. Sorry!
Our referral code is not currently stated anywhere, but that's a great idea; we'll work on adding it to the site in a place where people can find it. Anyway: on Amazon.com, the code is organifortran-20.
And in case you need the code for somewhere else, here are the other ones we've got right now:
organifortr02-20 : Amazon.ca
organifortran-21 : Amazon.uk
organifortr08-21 : Amazon.de