Google Earth.....don't leave home without it.
I have used it for a loooong time in planning hunts and looking at new areas. It's about the closest thing there is to actually being there. You can save a lot of driving, hiking and looking by using it ahead of time.
Like was mentioned you can couple it with your GPS and get waypoints marked, plan hunts and virtually know the area before hand even if you've never been there before.
Find the area, Zoom to the right level, rotate and tilt and then just "hike" up and down canyons and across ridges. Kinda like a virtual hunt/hike.;);)
If you don't have it, you can get it here.
Google Earth - This week's life on Earth