A fellow bread machine enjoyer, awesome. In case you have not considered this yet; you can make pizza dough in a bread machine too.
Yea sure, I mostly rotate between recipes that are based on dry goods, but can also have any miscellaneous vegetables added, so I can normally get whatever is cheap, or on sale, or use what I already have. Flexiblity is cheap.
I also normally buy bulk ingredients, and get the cheapest versions within reason. All beans are dry, vegitables not pre chopped, 10lb bags of rice, etc
Example ingredient lists are:
dal ( any lentils (preferably red), tomatoes, onions, spices, butter (for ghee), rice) (at so much dal at some point I rarely eat this anymore, but all the ingredients are dry so its always there)
ragu (some kind of bean (preferably a lentil), some kind of tomato, any pasta, garlic, any saute-able vegetable (namely zucchini), onion, spices)
chili (beans, tomato, garlic, misc peppers, onions, spices, can also add rice or pasta (egg noodles are pretty good))
hot bean soup (garbanzo beans, rice, onion, home made harissa paste, can add leafy greens like spinach)
...
Also soup + toast = fantastic
About twice a year I compare prices between local stores, but mostly I keep a mental note of prices of things and their substitutes every week at the store. In case you didn't notice, I eat a lot of the same stuff in different configurations, so this makes a big difference. For example, green lentils have doubled in price for some reason, so I buy split peas now. They require some pre soaking but then cook the same as lentils.
I split a Sam's club membership with a friend, which pays for itself with frozen fruit and onions alone (25$ a year).
I have also noticed, sales don't mean lower prices very often. Just lower than last week. For example, apples in season are quite cheap, but out of season it will go on "sale" for twice the price. I have in season charts for fruits and veggies that I keep track of. This is especially important for fruit, which generally I need to eat more of.
I also don't really eat meat or dairy, except cheese and butter. I could never abandon cheese.
Also I think most of this is in the ERE book? There's a food section somewhere. Also, the recipes in "Good and Cheap" (free pdf online) are all good.
I am also curious to hear what you all eat, and where the difference lies. I wonder if I live in a cheap area, or if have some sort of massive accounting error somewhere, lol.