GeoCommons, a powerful, free GIS tool and some data.
ArcGIS Online, a powerful, free GIS tool and rich datasource
ARC’s map archive, including maps of chapter jurisdictions, historic hazards, and many EEI sources
Have spreadsheet of addresses, want to plot in GoogleMaps: use BatchGeo
Have addresses, want to convert to lat, long: copy/paste into OneStep, for either a batch of addresses or just for a single address.
Have GPS file, want to plot in GoogleMaps: use GPSVisualzer
Spatial data sources
county outlines in KML
FIPS codes and counties, by State (from USEPA)
Flood Insurance Rate Maps (100yr and 500yr floodplains) from FEMA, including the current maps in .pdf and the partial set of digital maps, which may also be downloaded (.kmz) for viewing in GoogleEarth
NWS data as .kml/.kmz for importing to GoogleMaps/GoogleEarth, especially:
- Current Weather Warnings,
- Severe Weather Watches,
- River Gage Forecasts, and
- Experimental Local Storm Reports, which allows you to customize/download .kml of NWS storm reports.
Elevation at queried locations TerraFly; this site has detailed airphotos, and real estate info.