It's not something used by UK owners, we don't generally get very cold winters which would warrant a block heater.
When I worked in the industry we had provision for them in some markets, typically Canada and Scandinavia. I'm not sure how many forum members here are in those sort of geographical areas.
It might be worth you asking on a "Fit"/Jazz forum in the USA/Canada etc., though you might find they have a different engine to the European versions.
Let us know if you find anything, always useful to be aware of stuff.
