It's difficult. No two ways about it.
But here are some ideas to get you started.
1) Celebrity chefs always say things like 'cook with offal', 'use the obscure cheaper cuts of meat', 'make friends with your local butcher'...blah blah blah. All very well and good. But I (like most people) don't like offal - and how convenient it sounds so much like 'awful'. And I also don't have time for faffing around, even though I know the meat from butchers tends to be better quality. Here are some cheaper cuts of meat that are readily available in your supermarket. They may need cooking slightly differently.
Chicken thighs - cheaper than breast, and good if you're just going to chop it up anyway. The meat isn't as white as breast meat, so it's good if you're going to cover it in sauce (see sweet and sour sauce below, for example) or put it in a pasta bake
Beef brisket - bit muscly so cook it for ages
Lamb neck - ditto, good for stews and casseroles
2) As a follow-on from the previous point, whole chickens often work out to be a good amount of meat for your money. Roast a medium chicken and you will be able to feed four for two meals
3) Processed meats like mince and sausage are cheaper and often on offer
4) The 'reduced' section - my favourite hunting ground. Beware sell-by dates - after all, that's why the price has been reduced - but if you're just going to freeze it straightaway, what does it matter? N.B. Don't buy it if it's a funny colour or the packaging is damaged. I do not like green ham, Sam-I-am.
5) Frozen meat - if you're going to freeze it immediately, what is the point of spending more on fresh meat? I always buy my chicken breasts frozen, but experience with the value/ cheapest own-brand stuff is that they are pumped full of water to look better and weigh more. Obviously when you cook it, you lose the water and they shrink substantially. So it's worth spending a bit more so that you're actually buying a larger mass of meat.
6) Less is more. Or rather, less goes further. I will be posting recipes that help you make the meat you are cooking go further. Typically this involves bulking out with more vegetables and so has the happy benefit of being better for you!
Further suggestions on a postcard. Or in the comments section below.