You're probably thinking of Hotwire Savings Club or Connections123. Both require a membership in order to make purchases thru them. However, neither one sells the vouchers anymore and HSC will be closing soon.
The only source that I know of for vouchers is the dwtickets.com website. They sell Q&C vouchers for $16.95 + tax + shipping. It's not a bargain price and I wouldn't recommend it unless you intend to purchase a large quantity of vouchers and limit your dining to Beaches & Cream, the Pepper Market and Tangierine Café. Eating at any other location would probably cost you less to pay directly out of pocket than to use the vouchers.