don't use the pay service at terraserver (if you were) use terraserver.microsoft.com.
Also, download the free program usaphotomaps at jdmcox.com. It's a much cleaner picture with great zoom and features to lay out maps/waypoints/calculate distances etc. Very very useful for pre-scouts. Of course most of the usgs data is old, '98 in my area so if there's been logging, it's less useful. Good luck.