Petrol / Diesel Prices

[TVRJOA500M]

Hi everyone,
Looking for some help. With the thorny issue for everyone suffering fuel price increases countrywide we all shop around when and where we can. I use Petrol prices .com which I have found very useful for plotting trips in this country.
At the end of the month I am driving to Europe in a diesel Citroen C4 which normally achieves good (Approx 45MPG average on a run)fuel consumption. Travelling through France Switzerland and Italy.
Can anyone tell me on average general rates for diesel on the continent i.e - much more expensive or cheaper per litre. Also does anyone have a useful website that does on the continent what PP.Com does for us here?
I am not obsessive about this but just wondered how everyone else deals with this issue.

[sday12]

Avoid Switzerland, Northern Italy and Autoroutes IIRC.