The Genealogy Division of the Indiana State Library has a wide array of records and indexes that are invaluable to the researcher. These records/indexes include vital statistics indexes, probate, estate, and will records for many counties, census records, cemetery records, land records, and military records. The state library also has many Indiana county histories, as well as newspapers from around the state.
The Indiana Historical Society specializes in private manuscripts on a myriad of topics, not the least of which is an excellent collection of Civil War letters, diaries and other military papers.
I can also travel to the Boone, Hendricks, and Hamilton County Courthouses and the Indianapolis-Marion County City County Building to locate marriage records, land records, wills, or probate records.
Whatever information you are looking for, I can provide guidance as to the best strategy to obtain the information.