One of the more useful tools available to a geoscientist these days is Google Maps (or Google Earth). The maps can show where you might want to sample, where interesting geological features are (moraines, lava flows, river deltas, etc.). Overlays show terrain (topography), and roads, to aid you in figuring out how to best access the site.
Satellite images can show larger-scale features which may be fairly easily missed from the ground. Take for example the Manicouagan Crater in Quebec. The ring-like lake is 70 km in diameter, yet from the satellite/aerial imagery looks a lot like a crater.
With Google Earth, placemarks can be used to mark where samples were collected, and notes on the collection can be stored. This makes it very easy to go back later and see the field notes at a glance.
Although I haven’t used Google Earth or Google Maps for anything particularly quantitative aside from distances between sample locations, it’s a pretty useful tool. I enjoy playing around with it, too. There are some spectacular features out there, such as the lava flows of Glass Mountain, seen above. Can you figure out the relative sequence of the flows?