Just got back from there 1 month ago.
I visit about twice/year.
As stated above, the Euro is pretty much the same as the $.
Frankfurt, Munich & Stuttgart airports are no problem at all.
Frankfurt may look intimidating, but just follow the signs ( luggage, gate #'s, etc. ).
I would say you can get by with english pretty well.
( Easy for me to say, as I was born & raised ther & still speak german fluently).
Anything else you want to know, just ask.