How can I heat my house efficiently and cost effectively?

I am happy to recommend the Econo-Heat heaters/fires that can be purchased here in Uruguay.  The below pictured heater wall panels (a technology from South Africa) are imported here to Uruguay and run at the cost of leaving 4 x 100watt light bulbs running!  I have one in my kids bedroom and I leave it running all night to keep the room warm.    The Eco Sol company also sells the wall panel heaters (but I have not used their products before).

Another heating solution from the 'econo-heat' group of heaters to save on your electricity bill is this heater that heats up to 60m2:

It is an electric energy efficient heater that I use in our living area and other rooms (you can just unplug it and wheel it around to different rooms). 

Although the outlay cost of these heaters may seem expensive, since buying these and switching my UTE electricity meter to the split tariff, I have halved my electricity bill in winter!