How to find your lat and long coordinates

• Find the location on Google Maps, http://maps.google.com/. Search or navigate to your are of interest. Make sure that location is in the center of the map. Then, cut-n-paste the following code into the URL field of the browser: javascript:void(prompt(”,gApplication.getMap().getCenter()));
• Go to http://www.acme.com/mapper/. Type in an address or navigate to you area of interest. The lat/long of the center of the map is automatically displayed in the bottom left.
• Go to http://www.geodistance.com/. Type in an address or navigate to your area of interest. Click the map and the lat/long will be displayed at the bottom right. This site was created to find distances but you can find point coordinates just as well.
• Go to http://geotruc.net/. This site is quick and will return the lat/long of your mouse click in various formats (GeoRSS, GeoJSON, KML). You can also see the coordinates in the URL for testing or bookmarking that location.
• Go to http://www.earthtools.org/. Search for a place name, address or navigate to you area of interest. The lat/long of the center of the map is automatically displayed on the left.
• Go to http://www.geonames.org/. Search for a place name and click Show on Map. The lat/long of the center of the map is displayed in the upper right.
• Go to http://www.flashearth.com/. Search for a place name or navigate to your area of interest. The lat/long of any mouse click is displayed in the bottom right. You can choose among various mapping APIs to display.
• Use the Geonames Javascript API. You can enter any place name and the XML returned contains the lat/long. You can limit the number of returns as well. Examples are http://ws.geonames.org/search?q=london&maxRows=10 and http://ws.geonames.org/search?q=newark&maxRows=20
  
• Start Google Earth. This may be the easiest since all you need to do is search for a place name, type an address, or navigate to your area of interest and the lat/long of your mouse pointer is always located in the bottom status bar. There’s a good chance you can do the same in other virtual globes, such as NASA World Wind, Microsoft Virtual Earth, and ESRI ArcGIS Explorer.

I cannot comment on the accuracy of any of these methods. One of these days, I’ll test some locations against geodetic survey points like the HARN, or boundary markers, or against the most recent aerial imagery. Until then, take the horizontal and vertical accuracy of these locations as “usually close enough.” If you know of any articles that talk about the accuracies, I’d be happy to hear about them.