Will you throw rocks at me if I tell you there's a new edition of the Tough Guide about to be published by Firebird, and that it contains additional material?
Another great book for fantasy writers: Food in England by Dorothy Hartley. Absolutely indispensable. The Tough Guide to Fantasyland will tell you why the roadside inn's big iron pot isn't full of stew. Food in England will tell you that what's really in that pot is (1.) the inn's hot water supply; (2.) tonight's Pease Pudding and Spotted Dick (that is, one savory pudding and one sweet one), each tied up in its well-floured pudding cloth and hanging in the hot water on a string; (3.) various tightly lidded vessels containing stewing beef-bones, or frumenty, or salted codfish that's having the salt soaked out of it, or whatever else on the menu needs long, slow, moist cooking; (4.) miscellaneous Other.
She'll also tell you what kinds of dishes, ingredients, and styles of kitchen organization you could expect to find in different areas and periods, which by implication tells you huge amounts of other stuff about life in that period. Possibly the area where she's strongest is her comprehensive understanding that before the advent of fast, easy travel and large-scale marketing territories, the style of cooking, like the style of building and the local accents, could change every five miles. Even the breeds of sheep and pigs and cows differed from region to region, and were well-adapted to their area. Her illustrations are fabulous, like the page where she draws all the different regional shapes of loaves, buns, pasties, and meat pies, including the inscrutably cute Checky Pig.
Read Dorothy Hartley, and you'll never again have a full-size standing pork pie coming out of a one-woman kitchen in early spring, or mention bread being thrown out because it's gone stale. You'll know what laverbread is, and what's used to seal a sealed bottle. Your characters won't be living off the land the first year they set up to farm. You'll know what they buy and what they make for themselves. If they're foraging off the landscape as they travel, you'll know what they can find in what terrain at what time of year.
If you get the food right, it's amazing how many other details of material culture snap into place.
