I am actually surprised that 1.5 acres could "hide" 10 vehicles and 400 appliances from public view.
If the woman who claimed ownership of these vehicles and appliances is not the original property owner, and she did not have authorization from the owner and the city/state to dispose of these items in the way she did, SHE is the one who should be charged (with illegal dumping).
And the new owner of the property apparently has an environmental hazard on his hands (if there has been leaking of gas and oil into the soil) that will require more than a simple clearing of the land.
With that said, if you are being charged with felony theft, you need a criminal defense attorney who can fight your charges and perhaps turn the charges around to target the woman (who seems to be the only one actually guilty of a crime).
Here is a link to Florida's "litter law:"
http://www.leg.state.fl.us/Statutes/index.cfm?App_mode=Display_Statute&Search_String=&URL=0400-0499/0403/Sections/0403.413.html