End of Spit GPS coords are... 593595N 1512458W I give you the end of spit coords because I distinctly recall back a few years a big blue commercial boat set his auto pilot on his GPS coordinates for the Homer Harbor, and he went to sleep at the helm... Imagine his surprise when he woke up ashore, half way up the beach on the western side of the spit..../John
Here's a pretty cool link you can play with to find approximate lat/lon coordinates. The "crosshair" in the center of the screen is placed over the spot you want, and the coordinates are shown in the box on the right. You can change may display and zoom in/out. It's helpful in planning trips for boating or hunting.
Google earth and the garmin software are both good for "rough estimates" but I would not trust them for navigation in the fog or anything. You have to be sure that your GPS is set to the same datum as the Garmin software, as far as google earth I don't know what datum they use at all. I like to set my GPS up for the Alaska datum (NAD27AK) if I remember correctly but you have to watch other maps and such that use other datums. Many times I have recorded a track on my gps and plotted it on google earth and found that I was off a cliff or in a lake when I clearly was not. Same goes for Garmin MapSource, but once I corrected the datum it was much better.