I found this tip at http://www.gpsreview.net. Very handy. You can also use it to find other useful information. As the forum said:
1. I open Google Maps to the vicinity of where I would like coordinates.
2. I use my right click mouse button and select “center map here” from the drop down button.
4. I click the “go to the address in the location bar” button usually to the right of the address.
5. A popup appears showing the coordinates of the center of the map like this: (43.60336, -110.7362)
6. I right click on the coordinates the copy and click either “OK” or “Cancel”
7. I then paste the coordinates into google’s “search maps” text box, remove the parenthesis and click “Search Maps”
8. A popup appears with a marker for the centered spot. The popup has the coordinates in both Decimal Degrees and Degrees, Minutes, Seconds.
9. I refine as and if necessary and I have my way point for inserting into my GPS. I hope some of you find this useful. I know I do.
For more information, see: How to get GPS coordinates from a location in Google Maps – GPS Review Forums