"But I have heard people say they looked up friends in jail and they didn't appear there," There is a site where you can do a name search and see if you hit on the right person before you purchase anything during your
background search [See BackgroundSearch.com]. A few states do not publish criminal records on the internet, so that means the records are kept at the county level. If so, then you need to know every county that your subject person has traveled through in case he committed a crime there. However, if you use an information aggregator, like the one above, you should see all of the information in their database because they collect it from all 3,000 counties in the USA.