I faced the same issue. I live in 240v country so I picked up the Insteon hub and some switches in 240v thinking they would work with the Echo. Alas they don't since that 240v hubs is the generation before the Echo compatible hub. I thought I had bought something useless (in terms of the Echo) until I discovered this Home Automation software platform
www.openhab.org which supports all models of the Insteon hub. That still didn't solve the Echo problem but provided a web interface to the Insteon devices (in fact the Insteon devices do have apps for IOS and Android).
Then I discovered people had reverse-engineered the protocol that the Phillips Hue bulbs use and how the Echo talks to it. They exposed this as a addon to the OpenHAB software.
http://bwssystems.com/#/habridgeBoth OpenHAB and HABridge are Java apps that will run on Windows, Linux, MacOS and even a Raspberry Pi.
The HABridge software takes the Insteon devices and makes them look like Phillips Hue bulbs. So you can say commands like "Alexa - turn off the bedroom lamp" and the Echo turns off the associated Insteon devices. If you have an Insteon device that has a dimmer function that also works.
I also had some Dlink power modules
http://us.dlink.com/products/connected-home/wi-fi-smart-plug/that are only Echo compatible in terms of a Skill. That means you have to say "Alexa - ask Dlink to turn off the bedroom switch" which is a mouthful. But it turns out that the http commands that are used to control the Dlink have been reverse engineered and somebody had then written a Javascript script that can be used to control the Dlink.
What I did was take that script, install it on my server running OpenHAB and HABridge and now I can say "Alexa - turn off the hall light" and it will turn off the Dlink switch that is associated with it.
I initially ran this all on Windows 10 but since I didn't want to leave a Windows server running all the time, I ported everything to a Raspberry Pi running Raspian (based on Debian). I am not a Linux person but I am an IT person and it didn't take too much work. You can install the Java JVM quite easily and the Java apps just need to be downloaded to a directory and the associated shell script run. The Javascript was a bit trickier since I had to find all the modules that the code referred to (found them all on Github) and then it all worked fine.
I intend to buy more Insteon devices and Dlink switches.