I recently decide to invest in a new toy and have bought a Garmin etrex 20 handheld GPS. The plan was to use the gps in conjunction with google earth. I have found a few interesting features on GE that I wanted to investigate and hoped I could lift the co-ordinates from GE, plug them into the GPS and hey presto. The accuracy of the GPS would help in getting right on top of features only visible in aeriel photos, especially if they were the WW2 pictures on GE.
Well, that was the plan! Having had a couple of trial outings armed with the Garmin and coordinates from GE I have now discovered significant inaccuracies in the GE coordinates - in one trial on a known spot, GE was about 200 yards adrift, which may as well be 3 miles if you are trying to find a specific feature from 1945 photo in a modern ploughed field. Apparently the error in GE is partly due to problems with the way the photos are stitched together and how the photos taken from oblique angles are overlayed on the earth's contours.
Anyway, if anyone is using a similar technique to identify sites, I would still recommend GE, particularly the time slider, to find interesting features to investigate, however to get reliable coordinates, you need to go elsewhere.
After a few live tests, the most accurate website for coordinates is satsig.net. It's mainly for aligning your satellite dish but provides very good lat/long data using aeriel photos, . The mapping is much less user friendly than GE, but in my experience the coordinates data is pretty much spot on.
So, find the feature on GE, get the coordinates on satsig.net, plug them into the GPS and go for a walk
Lat - Long Finder: This page helps you find Latitude and Longitude