One of the problems I've always had with converting SHP to KML is there was no easy way to query the polygons directly from the map as is possible in a typical GIS program.
Well tonight I found a free program that will create a point SHP file from a polygon SHP file. It's called
GeoDa . With the point SHP file you can now query the polygon directly from the map view.
So with GeoDa,
Shape2Earth and
MapWindows GIS It's pretty easy to create a decent KML file from SHP files.
Tonight I did the Principal Aquifers of the US. It's a six meg KMZ so I won't post it here, but if you want to try it you can find it at the link below my name.