Best tip I can contribute is to "read this forum"
The better you know how to cook the less gets wasted and every possible dollar goes into feeding you and your family and not into the garbage.
There is a cooking contest I have heard about where every chef is given a basket of food and each chef must use all the ingredients to make a whole meal.
They have a couple of hours to prepare this meal.
Here's the catch; the chefs do not know what is going to be in their basket!
Each chef must be a "master" in order to use up everything they are given.
Go out and buy what is seasonally "cheap" and become a master of these ingredients.
Go out and buy what is "On Sale" and become a master of these ingredients.
Your meals will be distinct with the seasons and your food bills will go down when you cook with this "basket" you are given.
I once heard an interview with a well known french chef.
The interviewer marveled at all the things this chef could do with a simple onion.
The chef explained that when they were growing up all they had were onions.
So they became very creative with them in order to not get sick of eating them.
Simply put the chef used and used well, what he had in his "basket".
If you take this technique to it's limits, you will be able to go to the supermarket and buy whatever is "on sale", from meat to veggies, poultry, fruit and fish and come home with your bargains, what ever they happen to be, and prepare a solid, nutritionally complete, good tasting meal from your "basket"!