What are the best airfare deals when traveling from North America to Europe?
Possible carriers are:
Lufthansa: when flying to Germany
British Airways and Virgin Atlantic Airways: when traveling to United Kingdom
Aer Lingus: when on a trip to Ireland
Austrian Airlines: if you want to go straight to Austria
KLM: if you want to travel to Amsterdam
Air France: when flying to France
Alitalia: when traveling to Italy.
These were European carriers. And there are several North American airlines that travel to the old continent:
Delta Air Lines
American Airlines
US Airways
Continental to name a few.