Bon Homme County Of--tyndall, Extension Service 103 W 18 Ave Tyndall, SD 57066 Phone : (605) 589-3531 Business Category Government Offices-County Legislative Bodies Government Offices & Public Schools Bon Homme County Of--county & Home Economics Agents Office 103 W 18th Ave Tyndall, SD 57066 Phone : (605) 589-3531 Business Category Government Offices-County Government Offices & Public Schools