The Google campus now has 1 inch resolution in Google Earth. Several other areas are also updated

http://bbs.keyhole.com/ubb/showthreaded.php/Cat/0/Number/71406/an/0/page/0#71406

google earth is good but close up zooms are poor

Collection of 1000 file kmz for google earth of the best interesting place in the world. Preview, image and photo from satellite. Fly to. Tutorials.

http://www.sandrodiremigio.com/google_earth_3d/google_earth_3d_tutorials_satellite_image_kmz.htm