Check the Budget Board or Mousesavers.com for info on meal vouchers.
Basically you have to join a discount club which sells the vouchers. I believe there is a 30-day trial period, so many people will join for the trial, buy their supply of vouchers, and then cancel. If you forget to cancel, they charge you an annual membership fee in the neighborhood of $100.
The vouchers entitle you to a meal at one of selected WDW dining establishments. The amount that you will really save is often dependent upon where you eat and what you order.
I researched the vouchers a couple years ago, and it ended up just being more hassle that it was worth.
Scoootch: I'm sure it's too late for you to try the vouchers since your trip is so close.