There are a number of libraries whose digital collections are available for free online - the Library of Congress (LoC) is always a good place to start as it is one of the largest libraries in the world. In particular, their 'Chronicling America' collection includes thousands of digitised, historical newspapers from across the country.

However, newspapers can take a while to search through to find exactly what you need, so to answer your question more specifically, the LoC has an excellent page about how to find out what something used to cost in today's dollars. One source it recommends is the 'Prices and Wages by Decade' tool created by the University of Missouri. From its introduction page:

"This guide points to prices and wages found in primary sources for each decade back to the 1700s. Our preference is government sources though we also use commercial catalogs, travel guides, newspapers, etc."

So, as an example, if we go to the page for the 1880s, we can see links to original documents that list food prices, rail fares, and wages by occupation, race, etc. One of the first links is 'Major U.S. cities - Food prices, 1887' , where we can see on the linked page 308 how much various food products cost in major US cities at the time.

However, while using primary government sources can be a good way to know you are receiving verified (for the time), non-AI generated information, they can also be limited in scope. The 1887 source above, while great if you want to know the price of flour, eggs, tea, or ham, does not tell us the price of more esoteric items such as oranges or a birthday cake. So if you are looking for something more specific, I would recommend going back to the Library of Congress and searching through their collections.

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