Most of the states have some census records. It may be a handful of counties or just one or two years. Several states took a regular census on the '5' year [1855, 1865, 1875, etc.]. For a list of states with census years available see the following link: https://www.census.gov/history/www/genealogy/other_resources/state_censuses.html
The following states have not taken any censuses: CT, ID, KY, MT, OH, PA, VT
The state census can be a big help for those missing records between 1800 and 1900. Just hope your ancestors lived in a state with a good census.