title_body: Must try wines in Frankfurt region
upvoted_answer: I would spend your limited time and money just tasting wines from one region.  Nahe is a smaller wine region just west of Frankfurt, and I've found the wines there to be good quality, with individual charm (in other words, without the sense that they are mass-produced).  More info here
  
  By all means, talk to locals: the people you're visiting, the clerk in your hotel.  That's almost always a great way to discover something.