A good place to start looking for child care is the state website: www.in.gov/fssa/carefinder/ or a local childcare finder http://www.4csindiana.org/
Listed here are a few daycares and preschools that I've heard praise for from friends:
ECDC is a highly-recommended, on-campus daycare at St. Mary's and Notre Dame that provides care for children ages 2 through kindergarten. Since there is a waiting list, it is recommended that families contact ECDC as soon as they matriculate. For more information, consult http://hr.nd.edu/worklife/ecdc.shtml
Building Blocks Preschool, part of Logan Center, provides educational services for developmentally disabled children. http://www.logancenter.org/Services_BuildingBlocks.cfm
Growing Kids 17475 State Road 23 South Bend, Indiana 46635 Phone: 574-273-9048 http://www.growingkids.com
Friends 53062 Nadine Street South Bend, Indiana 46637 Phone: 574-273-1377 http://www.friendsdaycare.com/