The Soil Survey Geographic data set (SSURGO) from the Natural Resources
Conservation Service is considered the best available digital soils data
Soil Data Mart
NRCS's Soil Data Mart is the authoritative source for SSURGO data and reports. Since the data, especially the tabular portion, is evolving, it is important to make sure you have the most recent version from the site. NRCS includes a version number so that you can verify that you have the latest data.
Soil Data Viewer
This free ArcGIS extension from NRCS greatly streamlines the process of querying SSURGO data and producing reports and maps. Users who do not have ArcGIS but who have Microsoft Access can run a version that produces reports (no maps). NRCS provides complete installation instructions and a users guide, including help with obtaining and preparing SSURGO data for use with the extension.
For information on other soils data available in Minnesota, see MnGeo's soils information page.