Kathy is one of those women that they show on tv going through the grocery store with multiple carts, using a kabillion coupons and getting hundreds of dollars worth of groceries for free.
She has some good tips and a great website - http://www.howtoshopforfree.net/ which includes a coupon databank, which is great.
I think, however that Kathy has some better grocery stores in her area than I have here because I tried the coupon thing today at a store that doubles coupons and I used them with the store coupons. I did buy some other non-coupon items but they were on sale. I saved almost 50% according to their receipt, but their prices are over inflated to start with so I really don't think my savings were that good.