Also, add soups and stews to your menu. It is a great way to use up leftovers and you can make several gallons at a time, then freeze them in meal-size increments. In no time, you'll have a great selections of soups to choose from in your freezer on those busy night that you just don't have time to cook. A little bread and a simple salad and there is your meal.
Also, it is absolutely essential that you come up with a meal plan before you go shopping. I only plan one week ahead, but it keeps us from going out. I just had to get in the habit of looking at the meal plan before I go to bed at night to see what I need to thaw out for the next day. I just let things thaw out in my sink over night and I'm good to go for the next day. I use a small, magnetic dry erase board that I stick to my fridge. I can't tell you how much this helps me stay organized and save money.