If the arrest was recent
Start with the county jail
A person just arrested in Georgia is held in a COUNTY JAIL run by the county sheriff, not in the state prison system.
Many Georgia sheriffs publish an online jail/inmate roster for their county, so choose the county of arrest.
VINELink covers Georgia across participating jails and is the best single statewide starting point when the county is unknown.
Georgia has 159 counties, each sheriff running its own jail and roster (some with no online search); there is no unified statewide county-jail search, so use VINELink or the arresting county's sheriff.