Spreadsheet Mapper 2.0
A Google tutorial shows you how to enter data in an on-line spreadsheet to generate a set of markers in Google Earth and Maps and Google Maps API. Google Docs' web-based, collaborative editing allows your team members to simultaneously enter data and instantly publish updates.
"Using this tool you could: showcase your organization's projects, program sites or partners; map your offices, volunteers, or resources; or visualize your data on local, regional or global scales."
Time to create Lines and Polygons...
Excel to KML (now with Line and Arrows from GPS track logs) http://www.earthpoint.us/ExcelToKml.aspx
(copy and paste the code into excel or notepad and save as kml)