Here is a nice printable page for creating a price book to track grocery prices. My husband made something similar himself with excel, and we use it every time we shop. This has helped us keep a lid on expenses, and ensure we are finding bargains.
In addition, we shop with this list that has many of the ingredients needed for cooking with the More-With-Less Cookbook. It keeps our grocery store trips short, and inexpensive. We are less likely to impulse shop with a list. As an added benefit, it has helped with waste. We are able to take an inventory before we shop, and use things up before buying more.
I've mentioned this before, but we are still using the Allrecipes.com ingredients search when trying to find recipes to use up specific ingredients. What a budget saver this has been! It also helps with meal boredom...sometimes we get tired of the same meals. Allrecipes.com has helped us mix it up, as well as use it up.
See more tips at Frugal Fridays.