This post contains notes on building our 'Virtual Eye for the Sailing/Racing Guy' (VERG) race tracking program. The system takes multiple KML/GPX/KMZ files and assembles them into a file to be displayed in 3-D on Google Earth. The Google Earth screen can be embedded into your website. The VERG screen has a playback control which allows the playback, forward, reverse and playback speed controls. This control along with Google Earth's pan, tilt & zoom controls allows for great viewing and analysis of races.
The following html files are javaScripts modified from Google Earth's API home page at - https://developers.google.com/earth/ . The examples page at - http://code.google.com/apis/ajax/playground/?exp=earth#hello,_earth is where I got the following examples.
This javascript displays a specified area, viewpoint and standard Google Earth playback, and viewpoint controls - http://santacruznewspapertaxi.com/wp-content/uploads/2013/11/JavaScript010SailTracker.html
This javascript method gives you a view anywhere you want. createLookAt(lat, long, altitude, altitude mode, heading, tilt, range) To find your viewPoint in Google Earth set your position & viewpoint and then goto - Google Earth - Edit - Get Info - View - Snapshot Current View.