re: Does the Earth have too much water?
I don't see why you couldn't greatly change the environment of a desert (except that there would be environmentalists defenders of the desert).
California could pump sea water into the Mohave and Death Valley... Both I believe are below sea level.
They could both become inland salt lakes.
In the lakes, you could grow plankton or some other plant that could be used in the manufacture of alcohol or some other bio-fuel.
Water would need to be pumped both in and out of these lakes or else their salinity would quickly increase through evaporation.