One site that has become indespensible in my turkey hunting, especially public land hunting, is www.mapcard.com. It' s not free, but a membership is only pennies a day. I have only used it a couple of months and it has more than paid for itself. It allows you to access not only topo' s but aerials as well. One more plus is that it has map customizing features. For instance, one feature allows you to drag a symbol on the map, aerial/topo, and when you drop it, it instantly gives you the GPS coordinate of the position on the map. Then all you do is manually input the coordinate, select GOTO, and your hunting.