We should, of course, mention the great online resource- "Cyndi's List", which I have used for over ten years now myself. In checking the current postings for Midwestern states today, I came up with the following:
ILLINOIS- 247 hits, including the site on the 89th Illinois Infantry Regiment in the Battle of Pickett's Mill of 1864
INDIANA- 224 hits, including a locality listing either at the state level or alphabetical listing by county, to help you locate places of significance in your family history
MICHIGAN- 219 hits, including listings of libraries, genealogical societies, archives and museums in Michigan that may be helpful to your research
MINNESOTA- 205 hits, including cemeteries and funeral homes, as well as obituaries posted online
NORTH DAKOTA- 141 hits, including various state resources and the U.S. Adoption Registry for North Dakota
OHIO- 267 hits, including the Ohio Wills and Obituaries and the Ohio Cemetery Records project, which are so helpful for us with roving ancestors who passed through Ohio on their way further west eventually
SOUTH DAKOTA- 141 hits, including the South Dakota State Historical Society and African Ancestry in South Dakota site
WISCONSIN- 215 hits, including the Catholic Cemeteies in the Milwaukee Archdiocese site as well as the various genealogical societies ready to help you out.