Sources of free European national income and output data? What are good free sources of European National income and output data? 

By this I mean, amongst others: 
GDP and the variations of this such as; GNP, GNI, NNI and similar. 

Preferable in english and with formats that are easy to work with, such as .xls, .csv, .sdv.
The annual macro-economic database of the European Commission (AMECO) provides the data you need. 

The data is available for free, in formats that are easy to work with.