Call to enjoy

If we want data from a sales promotion form we have to enter it from a filled form. This takes time and can lead to errors. Also, all participants may not fill their forms entirely. What can be a way out? What if we asked participants to fill the form online, after which their coupon (number) will be emailed. Or fill it over the phone (single entry, by the tele-operator) after which the coupon number will be SMSed?