Click Bank Thank you Page with Lincense key

I want a custom script created to protect my thankyou page at clickbank. 1 : It should check whether the referrer url is from clickbank. 2 : It should provide a unique license key from a list of stored keys to each new customer. 3 : It should provide a link to the product which should expiry after 3 attempts. I thinks it is simple and can be easily done. Preference will be given to lower bids. Thank you,