The Sedgwick County Courthouse, in Wichita, has published a couple of useful guides to research.
The first, A Citizen's Guide to Open Records at Sedgwick County, covers what is available from the county in the various departments of the courthouse, including property records, tax records and maps. It also covers what isn't available, particularly vital records, which are available from the Kansas Department of Health & Environment Office of Vital Statistics, and marriage records, which are held by the District Court rather than the county. Of course, the county and the Court are all in the same building, so this may be a distinction that only a Freedom of Information Officer really cares about. (The brochure doesn't mention that pre-1917 marriage and divorce records are on microfilm at the Midwest Historical and Genealogical Society.)
The second, A User's Guide to Real Estate and Personal Property Assessment Rolls on Microfilm, is a finding aid for 36 reels of microfilmed records from 1876 to 1898. These microfilms are available at the downtown Wichita Public Library or at Wichita State's Ablah Library.
The District Court website isn't as helpful to researchers, so a call to the appropriate office (such as Probate) may be necessary.