I am going to be in Osnabruk, Germany till August 23, 2012. I would like to take an excursion to Amsterdam. Are there bus excursion operators in Osnabruk that offer Amsterdam tours? (maybe some network which operates all over Germany).
Considering that there's a direct train connection from Osnabrueck to Amsterdam Central Station, I'd just look for any tour operator where you can book Amsterdam tours separate from the ticket to Amsterdam. They'll just give you a meeting point that's well-reachable (probably Amsterdam Airport). That means you'll have to travel another 15 minutes from Central Station to the airport. Can't miss, really.