Has anyone successfully built a 'Tesla Generator'?

My dad is thinking of buying plans from the internet to build a ‘Tesla Generator’ – with a view to generating our own electricity.

All the websites we have viewed so far insist on a payment before seeing any of the plans.
They dont seem that expensive, but of course we are always worried about paying for something you cant see first (my view is that these are very often a con), and if the plans are as good, and as useful as the adverts purport to be.
I’m wondering if any Fluthers have built a Tesla Generator or anything similar?
Did it work? Has it been worth it?
Where did you get your plans from?

Any advice would be greatly appreciated..