SEMA has available Q3 Floodzones (76 Counties Only) coverage of the state by county (in MapInfo and ArcView formats).
To request any of the Q3 Floodzones, you can email Randy Scrivner or call him at 573/526-9141.
If you are looking for more information, you can go to the University of Missouri's MSDIS Web site or to the CARES site and download most county information directly in ArcView and MapInfo formats.
ESRI through an agreement with FEMA also has multi-hazard maps and information available that users can access at www.esri.com/hazards or www.fema.gov
NOAA Map (This map is
downloadable in .pdf format.)