ICPSR (data hub)
This is the data hub that I was talking about in class, where you can find many datasets that collected by others. Many of them are well-known, high quality datasets. This is a great place to explore secondary data, if you want to use secondary data to do your research. And, it is also a good place to find sample measurements if you want to collect primary data on your own.
Click on ICPSR (data hub) to open the resource.