Unfortunately there is no equivalent to CL sites in Germany. However, we prefer small quiet sites, too. The ADAC campsite guide features a symbol for particularly quiet sites and I've found it very reliable, particularly when they they only have a relatively limited number of pitches. If you have a rough idea of your itinerary, you can
email me and I can have a look what I can dig up for you. However, We're touring the UK with our caravan at the moment and it will be while before we're back home and I have access to all information.