Create a map from a published Google Spreadsheet

http://gmaps-samples.googlecode.com/svn/trunk/spreadsheetsmapwizard/makecustommap.htm

Embed a dynamic map of a public Google Spreadsheet on your webpage. After loading in your spreadsheet data and customizing the map, you can copy the generated code into your webpage. An example spreadsheet's data and map of great Seattle restaurants has been pre-loaded. You can view the original spreadsheet in HTML or XML.
This wizard uses the Google Maps API and Google Spreadsheets API.

Load worksheet data

To find the spreadsheet and worksheet ID for your Google spreadsheet:

• Save and publish the spreadsheet (Warning! Don't publish private data!)
• Click on "More Publishing Options," change file format to ATOM & generate URL
• The URL should look something like 'http://spreadsheets.google.com/feeds/list/[spreadsheet key]/[worksheet id]/public/values.'
• Find the parts of the URL that match the example below and paste them in.

Click "Load Worksheet Data" button when done. If your worksheet loaded successfully & you're using Firefox, you'll see a snapshot of the column data below. Note that the first row is treated as the header row - so it's best to put descriptive column titles there (e.g. "year", "revenue").

Spreadsheet Key:

Worksheet ID: