Chick,
That would all depend on the software you’re using. I assume you’ve tried looking at their FAQ? We build all of our own commerce sites from the ground up so we have the flexibility to add coupon codes or anything else that arises (and something unique always does show up). It’s possible that if you’re using an off the shelf type system it may not have coupon codes as a feature. Maybe just ask them to use the second address line to mention they’re a member? You might also be able to add a duplicate product at a lower cost and then “hide” it from your site and send everybody here a special URL to get the discount. Just don’t discount it to the point that if a search engine picks up on it and starts linking to it somehow that you’ve losing money!

Thanks Matt I’m using the software from web.com they have no info on the subject so I may have to wing it.