Everything in Shapeways is stored in Dollars, calculated in Dollars etc and converted as needed.
To get the euro equivalent I am afraid you will have to do a conversion - in the simplest instance Google can do this, e.g.
type in the search box: 2.99 usd to eur
Otherwise you will have to make a spreadsheet or program and access the correct rate.
The good news is that the rate never changes by that much, so once you have calculated the equivalents once you will have a good idea of the costs in euros. Unless your models are very big the exchange rate fluctuations will only mean a difference of a few cents at any one time.
Also related:
- because all prices are stored in dollars, the prices of your models in your shop and the amount of the markup will change with the exchange rate;
- I cannot 100% be sure but I think that the price of silver changes over time because of the raw material cost.
Good luck!