Our In-house Information Center has data from the 1980 and 1990 census. Information is available by county, city, census tract, and block group.
Some information is available by block.
The Census Bureau's web site has an enormous amount of information. If you need data from the 1990 Census, select the Access Tools option from their home page and then select 1990 Census Lookup. At this point you will have a choice between obtaining data from STF1 or STF3. After selecting from STF1 or STF3 you will then be given a very long list of subjects. This is where you can select the geographic area and the data you are looking for.