This article is an EXCELLENT overview of how a family can cut costs. We've used MANY of these ideas.
My favorite "get my mind thinking" about cutting cost are Hillbilly Housewife's $70/week mealplan or her $90/wk mealplan.
This has great ideas http://www.menus4moms.com/frugal/meals_for_hard_times_1.php
My kids LOVE Clara and BOY does she help you get in the spirit of back to basics. SERIOUSLY educational videos http://www.youtube.com/user/DepressionCooking