If you want somewhere familiar yet different, Ireland or Britain is the obvious choice. Perhaps not the main centres though if you want to be creative. Further out in place like Scotland and the West of Ireland. Naturally I'm going to sell Ireland. There is even an American college in Dublin. I've no idea what's it's like.
http://www.amcd.ie/But if you want to avoid the big city. You might look at Galway
galway I've just moved here and it's a cool enough relaxed town with quite a few American students. You don't have to go to college of course and in theory you can't work without a permit. But that never stopped anyone particularly in casual jobs. I never heard of an American being deported for working illegally. There is a creative atmosphere, writing and art being particularly favourably looked on in this country. (Also talking and drinking:aok )
But if that doesn't suit as Ro says Eastern Europe is opening up all the time. There seems to be lots of Americans in Prague.
Spain is another country to be recommended. Sunshine and a very relaxed people tolerant of foreigners. Plus some magnificent countryside. Most people in Europe would love to retire to Spain.
Don't discount France either particulary away from Paris. But you really do need to speak a little French or a least pretend to. The French I notice are more likely to speak English to you if you at least try to address them in French.