I was reading my blog feed on Feed Demon, when I came across a post from Free Genealogy Tools, and they mentioned finding out what items cost in your ancestors' time. The article mentioned a website which has historic prices of goods in Morris County, New Jersey, from 1900 to 2009. That's pretty doggone specific, and my family is not from anywhere near Morris County, New Jersey, but it is obvious that we all can benefit from checking old newspapers, from the place where and the time when our ancestors thrived.
All sorts of newspapers are available online, at a variety of websites. For those of us who live pretty much in the area where at least some of our ancestors lived, the local public library is also a resource, with newspapers on microfilm. A local university library may also have relevant newspapers on microfilm, and most good-sized libraries will have such papers as the New York Times, the Chicago Tribune, or the Los Angeles Times, for example.
Local papers will be good places to look for grocery prices -- the sort of thing that can vary from region to region. One may also find in the grocery ads specific items that may have been regional in character, as well. Might this spark a memory of your mother or aunt or grandmother fixing collard greens or a New England boiled dinner or fresh-caught salmon?
National papers can be places to find prices of nationally-distributed items, such as automobiles or clothing. Another source for this information would be the magazines of the time -- The Saturday Evening Post, Life, Look, or other magazines popular at the time your ancestors flourished. When I was a teenager, I used to babysit for a doctor who had a collection of old Vanity Fair magazine from the 1930s, and I used to enjoy looking at the ads as much as I enjoyed reading the articles and stories.
Another item which could be amusing to investigate is the advertisement of pharmaceuticals, supplements, and patent medicines. Did you ever see a bottle of Lydia Pinkham's in your grandmother's medicine cabinet? Did your grandfather use Hess Hair Milk to keep his hair from turning grey? My husband's grandfather did, but when he was hospitalized one time for a few days, without access to the preparation, his hair turned snow white! I guess the stuff really worked!
If you have any of your ancestors' high school yearbooks, from about the 1920s onward, you will find in them advertisements for items the students or their families might have bought, the "trendy" things of the day. And city directories will also have advertisements, and in addition, you can pinpoint the location of stores in the town with the address listings. Most city directories also have maps, so you can get a visual idea of where your ancestors might have shopped for the items or services in the advertisements.
If you are as keen as I am on fleshing out your ancestors' lives with social and economic history, get thee to the newspapers! You may also want to look at the Free Genealogy Tools website (check the link in the first paragraph of this entry). They have a lot of great suggestions, and links to all sorts of sites rich in social history resources.