My husband and I are both on disability. Our current disability income is pretty decent, but about six years ago, before either of us were on disability we were in a very tight situation. We had to file bankruptcy mostly because of my medical bills, and hubby losing his job. I was losing my job, because of my illnesses. We moved to Wisconsin were hubby found work, and had to live on one income. I filed for disability, but it would be another 9 months before I would be approved (didn't know that at the time, though). Hubby made just a few dollars more than the cut-off point for food stamps, but our medications (even with good insurance) were costing us hundreds of dollars per month. It wasn't unusual for our food budget to fall below $50 for both of us, for the whole MONTH. We ate lots and lots of beans and pasta, and we learned a lot of ways to save money.
First, I'll recommend the Tightwad Gazette books. Ideally The Complete Tightwad Gazette by Amy Dacyczyn (because it's all three books under one cover), but any of them will do, and your library probably can get a copy for you.
There are similar books under different titles, and frugal living and cheapskate/tightwad/miser/saving money websites. Essentially tips on how to save money ins every possible way.
I've talked about this a lot before, so rather than try to remember and repeat everything, I'd suggest you browse the shoestring meals forum. Where a bunch of us have shared money-saving tips. You may only be able to use one tip in ten, but every little bit helps.
Another great website is hillbillyhousewife.com website, especially the dieting on a budget section (using an exchange plan).
http://healthy.hillbillyhousewife.com/category/articles
We were very lucky that we never lacked transportation. Not only did we have a car, but our area has inexpensive public transporation as well.
There are so many things we learned and did that I can't even begin to list them all, probably the most important was learning where the bargains were and developing a system that maximized our ability to take advantage of them.
Just as an example, we usually started our monthly shopping at a store kind of like Big Lots, where we looked for bargains and only bought items that were a bargain (not only money wise, but healthwise too. Candy was really, really cheap, but with both of us having blood sugar issues that wasn't a good option). However, we found some great bargains on healthy foods too - such as gourmet dried beans for .29 cents per pound bag.
Unfortunately, overstock stores are like garage sales, in that you can get amazing deals, but you never know what you will or won't find, so you have to be flexible.
As I read in the Tightwad books, I kept a price book. Everywhere we shopped, I'd use the cash register receipt or even would take notes while I was shopping. It helped me find and recognize the best bargains.
We did a lot of shopping at Aldi and Walmart. We bought yellow-tag meats at Walmart (discounted, but still good - as long as you used them or froze them within a couple days).
We shopped ethnic markets. The best price for rice, asian vegetables, and asian seasonings are in the Asian groceries. We can buy a quart of gourmet mushroom soy sauce for the price of a tiny bottle of store-brand soy sauce.
Mexican markets have great prices on dried beans (especially black beans).
We buy spices from bulk shops (either scoop-your-own places, or baking supply stores where they've repackaged bulk spices into small plastic tubs).
We shopped health food stores for sprout mixes and tvp. TVP granules (soy protein) looks like grapenuts cereal, but reconstitutes with hot water to a ground meat substitute. Hubby doesn't like the plain tvp flavor, so I would brown it with cheap (fatty) ground meat. Because tvp is fat-free, the tvp/beef mixture would be fattier than the tvp alone (but more flavorful) but as lean as more expensive ground meat. TVP is usually (in my area) about the same price per pound as mid-grade ground beef - but one pound of tvp is the equivalent of 3 to 4 lbs of ground beef. Using tvp alone would save the most money (and calories and fat), but the beef-tvp is a good compromise.
Sprouting mix is also a great health bargain. You can sprout in almost any glass or plastic container. There are instructions online. Sprouting mix prices seem a little high until you realize just how many sprouts a package of seed mix will grow. Only only a couple tablespoon of sprout seeds makes a lot of sprouts. They're great as a salad, as an ingredient in a salad, on sandwhiches, tossed into soup, or stir fried in dishes. They grow fast (about three to four days for most seeds. When they've reached the size I like, I just put the jar into the fridge, and pull out what I need.
We buy apples in bulk bags, they're cheaper that way. And we store them in the fridge (not only do the apples last up to 10 times longer, they taste better and have a crisper texture cold too).
Some stores discount bananas once they turn yellow. We buy them and store them in the fridge. The peel gets black, but the fridge slows down the ripening. Or if they're too ripe to eat fast enough, I'll peal them, cut them into four pieces per banana and freeze (perfect for using in a smoothie).
It's really all about finding hundreds of ways to save a few cents, which add up quickly.
We make homemade soup often.