This page is an attempt to replicate the functionality of the real KML Embed Gadget provided by Google, which is currently non-functional. However as it was Open-Source, was able to steal the code, and package it up in a basic container - enough to make it functional. Based on this XML file.
The iframe generated by this tool, comes with absolutely NO warranty, Google could discontinue, or break the Google Earth API and/or Google Maps API v3, that this relies on - at any time. This feature is in no way endorsed by Google Inc.
... in fact (as of Dec 2015) Google HAVE discontinued the Google Earth API. This tour gadget non longer works. See their blog post about it.
Can still use the plain KML Embed gadget, as that has a 2D (Google Maps API) version.
There is also a Fake KML Embed Gadget Maker.Instrunctions..