I, also, checked out Google Earth and saw mostly fuzzy stuff up close. Then I checked into TopoZone Pro = the advanced version. It doesnt zoom way in & out but it has several very desireable features.
Like overlapping an aerial map over the topo map. Now I can see just where things are on the aerial view.
Interactive curser - which means it will give the GPS numbers when you move all over the map with the mouse pointer.
A huge map blow up besides 2 other sizes. Lots of choices of feature settings and other thingsa you can do but I probably wont use them. Others will. Costs 50 bux per year. I'll more than get my money back as I locate detecting sites in the woods, etc. Steve in so az