Use the Data & GIS Research Guide to learn more about data & GIS
Use a research guide from Penn Libraries that focuses on your discipline.
Identify an organization that studies the topic of interest and investigate their publications. In many cases this is a government agency, which may have data available for download on their website. See FedStats for a list of government agencies that collect data.
Search a data archive. Data archives are organizations that preserve research data for reuse. Some are subscription resources provided through the library; some are freely accessible.
Using a library database, find related scholarly articles and look to see what data sources the authors mention. Find databases by subject.
Online or in the library catalog, find relevant statistics and seek out the data from which the statistics were drawn. Try searching ProQuest Statistical Insight or Statista. In Franklin, try searching for "your subject" AND statistics by Subject. In Google, try for particular file types. For example, add filetype:csv to your search terms.