I will be in Munich for 3 days and I would like to join a Neuschwanstein and Linderhof Day Tour from Munich but I don't want to book it online because I don't want to be tied down to certain date especially if the weather is not pleasant.

Can anyone point me to a tour agency or operator in Munich where I can book the day trip?

Your hotel concierge or front desk can give the choices - they have all of the brochures - and provide tickets.

When we went in April, There were big tour buses lined up outside Karstadt department store, right across the street from the train station every morning. I remembered there were even bus stop signs showing what kind of tours they have. We booked online in advance (the Neuschwanstein/Linderhof tour) so I didn't read the signs, but I would guess there are contact information on there. There was also a tour agency booth inside the train station (open during the day only) near the north exit, and I'm sure your hotel receptionist could help also.

I also booked on line for this tour and picked it up outside the Karstadt department store. Here is the link to the tour operator http://www.grayline.com/things-to-do/germany/munich/ but I couldn't locate a physical office to walk into. I also don't recall a booth or office at Karstadt but wasn't looking for one. Maybe call the 800 number on the website if you aren't staying at a hotel.

Thank you! I will be staying in an apartment so I won't be able to ask a concierge for help in booking the tour.

There is a TI office along the front of he train station. Also, concierges make a commission off of tours they sell so they would not be particular about whether you wee staying at their hotel or not. Pick a nice hotel and walk in and talk tonthe concierge. Enjoy your trip.