try
www.supercook.com put in the ingredients you have and it will give lists of recipes you can make out of what you have, maybe with a couple of other things such as butter or oil etc.
If any of your friends are in a similar position, when you are buying food get the bogof offers and split the price of each item between you so you are getting it at half price.
Go to your local library, find out about the local nature what is available for you to pick e.g. different kinds of berries, nuts etc.
Quite often in libraries you can find out about local courses or nature walks which could offer you the chance to get this more safely.
End of nights is when most places will reduce foods, more often than not they can be bought and frozen or cooked that night for use the next day.
When making a meal try and cook at least one other portion that you can freeze and just defrost and microwave another night saving you cooking time and money for cooking. cooking in batches and portioning it means you can cut costs, as well as on electric/gas you can then buy food in larger amounts which is normally cheaper.
If cooking for example a chicken, one night a roast, another night part chopped up for a stir fry, another night wings and parts for a paella, use the carcass for stock, any left over chicken make it up with a basic white sauce and use it in either a pie or make crepe pancakes and use it as a filling. 1 chicken for my bunch though only covers 2 dinners and stock, but if your are single you can get sevreal meals and a few lunches. All you have to do is freeze it so you are not getting sick of it and alternate meals.
Greenstar mention phoning up and complaining about foods, another way is phoning up and complementing them and saying that you wish you could buy more etc but funds are low etc, they still send you out vouchers, I normally found they sent out more for being nice and straight forward.