I'm, having to penny pinch for meals as well so feel your pain.
I shop at Tesco and get their cheap meat and veg and pasta and rice etc. the frozen 1kg chicken breasts and 2kg drumsticks/ thighs and £1.29 sausages are a god send for those of us who can't afford organic hand reared products.
From these I can do various chicken stews/ soups (defrosted chicken drumsticks/ thighs with loads of cheap veg and spuds and stock cubes (50p a pack). I add in their pasta as well to help stretch it. Just put in whatever veg you have, even the sad near death ones.
Savoury rice is really easy and cheap. finely chop an onion and fry in oil, add in a grated stock cube and however many tablespoons of curry powder you like, some tomato puree (add in a bit of sugar as well it helps) add in rice and fry for a few minutes then add in boiling water and simmer for about 15/ 20 mins until all the water has gone (remember to stir near the end so the bottom doesn't catch). I add in frozen peas and sweetcorn and you can add in chicken or other meat if you have it.
A tin of chopped toms, fried onion and a bit of sugar makes a lovely easy and cheap tomato sauce for pasta.
I use this for a chicken and bacon pasta bake (bacon is the cooking bacon about 60p) with a crunchy topping of whizzed up slice of bread and grated cheese. Just fry some chicken, bacon and chopping onion, cook pasta for half the recommended cooking time. Add everything to a oven proof dish, add in any veg u fancy and sprinkle the topping on and bung in oven for about 30 mins.
Instant ramen noodles are bloody amazing as you can make soups from them. add in whatever cooked meats/ veg you have hanging about. I use a potato peeler to thinly slice up half a carrot and add in a couple of thinly sliced mushrooms and thinly slice onion. Takes minutes to cook and is very filling.
Also cheap frozen sausages make really good sausage casserole. Cook them, add to slow cooker or on the stove/ oven in a pot with fried sliced onions, tin of toms, tin of beans and cut up spuds. cook slowly for an hour or so on the hob/oven (stir every now and then) and eat with some slices of bread to mop up the juices. :)
Good old cheap mince can make loads of meals.
mince stew (just like the chicken stew but use beef stock cubes)
Mince and onion with mash
burgers (we have them in cheap pitta bread with home made potato wedges)
Taco mince with savoury rice (just cook the mince with onions and add in some cheap packet taco seasoning and you can use the rest of the taco seasoning in the savoury rice instead of curry powder)