Software suggestions needed

I've just obtained access to approximately 90,000acres of land that me 
and other planers are choosing to develop into housing subdivisions. We 
looking for a consumer or prosumer level software program so that we can 
start preliminary drawings to develop a vision on our own before going 
to the architect for the final plans. Can I get some suggestions as to 
some good software programs on our expertise level (NO autoCAD, LDD 
etc...). We want to show housing lots, roads/streets,a huge lake or 
lakes, wooded areas, ect...