County government in Nebraska

County government in Nebraska is organized in two ways:
Township counties: the county is divided into townships and governed by a 7-member board of supervisors. 27 counties are governed this way.
Commissioner counties: the county is governed by a 3- or 5-member board of commissioners, but is not divided into organized townships. 66 counties are governed in this way.

 Elected county officials 
Board of Commissioners (commissioner counties) or Board of Supervisors (township counties)
County assessor
County attorney
County clerk
County sheriff
County treasurer
Register of Deeds

Other county officials (such as the county Surveyor and the election commissioners) are appointed; in smaller counties, these officials may be shared by multiple counties.

Other websites
Nebraska Blue Book 
Nebraska Association of County Officials 
Government