I think I've mentioned before my love for the Tightwad Gazette. Eric found this for me at a used book store and we leave it around pretty much all the time for inspiration and encouragement. I love that this book doesn't really tell you that you have to live a certain way. Rather, she encourages you to set a goal and look for ways to reduce spending so you can increase your savings to reach that goal. For most people it is easier to save more than to earn more. She further says that the most important things you can do are the little things that happen every day. She reasons, correctly, I think, that you seldom have an opportunity to save $100 but every day you have many opportunities to save a few pennies. And those pennies add up. Developing the habit of saving money in small ways also trains you in frugality so that when the bigger opportunities to save come up you don't feel like you are missing out when you choose a much less expensive option.
I doubt that Amy Dacyczyn invented the price book concept, but it is a centerpiece of her lifestyle and one that I recently adopted. It's simple, really. Make a chart of all the food you buy and all the stores you could reasonably shop at. Then record prices. I used to think that I just "knew" where things were the cheapest. When I made my pricebook I found that my instincts were correct in some cases and not in others. When a friend recently introduced me to her neighborhood food co-op I was able to take the price list and quickly find the things on it that were a better deal than what I was currently paying. I don't happen to shop any place that has sales but if you use regular supermarkets you can note the dates of good sales on the price book. You might notice that peanut butter is on sale every six weeks so you buy a six-week supply then. You might notice that butter bottoms out twice a year and decide to stock the freezer.
Sometimes driving around to a bunch of different stores each week can negate any financial savings. I get my food from seven different places. Three are food co-ops where we place monthly orders. Two of those are in my neighborhood and are a great way to see my friends. The third is in a good friend's neighborhood and its a great excuse to see her. The other four places are stores. I use Trader Joe's for regular shopping. I use an Asian market for produce when I'm buying enough produce to make the extra trip worth it. I use Safeway when I need white vinegar, chocolate chips, or ice cream. That's the store in our neighborhood so it gets hit up when we run out of something last minute. I also go on occasion to The Glut (motto: still cheap, still funky). That used to be my main store but I've found almost everything there for better prices. I'm a little sad about that, actually, because I always liked shopping there and wondering if they could tell how conservative I was just by looking at me. They have the best prices on supplements, so I go there when we're sick or I'm pregnant.