Add a How did you find us? field to customer account

[anthar]

Some of our customers are being referred to us by their physicians and we want to track those customers. We'd like to add a "How did you find us?" field either to the createaccount page or to the checkout page. Seems like it might be easier to add it to createaccount. Has anyone done this before? I'm using ML8. Thanks!

[anthar]

No one's replied to my post, so I dug in myself, and added a note to the string resource for the Special Orders / Gift Message field. Not very elegant, but seems to be the only thing I have some control over. Asking customers how they found us is so important - can't believe there isn't a simple way to ask it.