Google Maps do not display latitude and longitude values, but there is an easy trick to get these numbers. This technique will provide the latitude and longitude coordinates of the center of the map displayed by Google Maps.

Looking up an address in Google Maps will center the map on that address if it was found. Because this trick provides the latitude and longitude of the center of the map, moving the map around manually after that will change the center position and this technique will not work accurately.

When the location you want is in the center of the map, copy and paste this code into the location bar of your browser and press enter:

javascript:void(prompt('',gApplication.getMap().getCenter()));

A little dialog box will pop up displaying the coordinates which can be copied and pasted for use elsewhere. This code can be bookmarked and then used in the future by selecting the bookmark.

I love this hack