The Census Bureau's, Decennial Census of Population and Housing provides PDFs of the census volumes, including all of the supplementary publications, from each decennial census.
If you prefer hardcopy editions, use the library catalog to search by subject heading -- e.g., United States Census, 3rd, 1810, United States Census, 4th, 1820, etc. The results will include all of the reports we have* by the census bureau during that census year (including supplements to the main Census of Population/Census of Population and Housing reports).
If you are looking for older, hardcopy editions of the Census of Population/Census of Population and Housing, see the links, below.
*The library may not have every volume of a decennial census or every supplementary report published.