There's also APRS if you happen to be a ham radio operator. With APRS, your gps is connected to a ham radio transmitter with a device like Tinytrak http://www.byonics.com/tinytrak/ (or TNC) . Receivers all over the United States (and rest of the word) then broadcast your position to the internet, where it can be seen on many different APRS map applications. One that uses Google Maps http://aprs.fi/

And here's a solution for Google Earth: https://aprskml.dev.java.net/