Welcome to the forums... As a fellow European I welcome you to the club.
I never imported the car. It was sitting at a dealer over here, and I was looking for something different. Guess you just gotta bump into stuff like this. As to taxes... There is a BPM cost here in the Netherlands (which is basically taxes on new vehicles) which is a hefty percentage of the value of the car. Which gets added to the standard list price for the Netherlands.
In all honesty it doesn't make any car that much more attractive to buy, especially once you start comparing the price of a vehicle with the price of a similar vehicle in the countries around the Netherlands. Then again, taking the BPM off the price (to comply with European countries and legislation) would devalue any car massivly. Not something we Dutchies look forward to, despite the fact that it'll make cars cheaper, which is good I suppose.
Further taxes include roadtax, aswell as a massive load of taxes on the gasoline. So in essence this car is making the government really happy... If I leave the environmental aspect out of it.
As to finding information... There's plenty on the web! Hit Google and browse a bit. You'll likely find anything you'd want to know.
Lastly gas mileage... Citydriving a 4.6V8 (stock) it comes to 18 Miles per Gallon, which equates to 7.65 Kilometer per Liter. Highway driving can improve it up to 26 Miles per Gallon (or 11.05 Kilometer per Liter). The actual usage is more or less based on what you drive mostly (city/highway) and how heavy your foot is.
If you keep to 20 Miles per Gallon as the average usage, that would equate to about 8.5 Kilometer per Liter.
Run some conversions yourself to your hearts content:
http://www.onlineconversion.com/fuel_consumption.htm
Just make sure that you use the US (liquid) gallons, and not the UK ones... They differ. And as it is an american car you'd need the US measurements.