http://blog.iharder.net/2011/01/19/locate-your-mac-laptop-if-it-is-missing/
LocateMe is the key here have a look.
USAGE: LocateMe [options]
Version: 0.2
Outputs your current location using Apple’s geolocation services.
-h This help message
-g Generate a Google Map URL
-l Generate long, multiline format
-f format Generate a custom output with the following placeholders
{LAT} Latitude as a floating point number
{LON} Longitude as a floating point number
{ALT} Altitude in meters as a floating point number
{SPD} Speed in meters per second as a floating point number
{DIR} Direction in degrees from true north as a floating point number
{HAC} Horizontal accuracy in meters as a floating point number
{VAC} Vertical accuracy in meters as a floating point number
{TIME} Timestamp (with date) of the location fix
{HOST} Computer hostname
Pretty cool! Credit goes to Robert Harder at iHarder.net for the LocateMe program. You can find other useful scripts in the post above...
