I found the resource files inside the Sitefinity\ControlTemplates\News\LocalResources\...
I copied this and created a new file for my 'nl' language. Works fine!
But... there is one label that isn't inside the resource file and that is on the SingeNews page:
|<p class="author"><em>by: <asp:Literal ID="Author" runat="server" /></em></p> |
So, I'd like to translate the word 'by' also. Could this also be a server control and be added to the resource mechanism?