Boarding Kennel I can highly recommend Heinz Diemert and Anette Schnurr.
They know dogs in and out. Used to do Schutzhund and Agility. They are personal friends of my family so I can highly recommend them. If I'd leave a dog with anyone than it's them. They are right next to the Coleman Barracks in Mannheim and have a lot of American Clients.
you can find the contact info under impressum, they charge 20 euros per dog a day.
As a Vet I can highly recommend Dr.Dominik Roeder out in Bensheim. It's half an hour drive via the Autobahn and Bensheim but he's absolutely worth it.
He takes care of all of my families horses, all the dogs and he's very reasonable with what he charges, not like the Heidelberg clinic that is charging ridiculous amount of money.
Dr.med.vet. Dominik Roeder
64625 Bensheim (Bensheim)
phone number: 06251 3539
The Club in Edingen Neckarhausen welcomes english speaking families, however the language barrier sometimes made it hard and none of the people I brought to the Club sticked to it. So I am not sure what is going on, however there is one club in Mannheim right next to the Coleman Barracks that has some well educated people who know the language very well and they are always friendly and open minded.
Their helper is one of the best you can fnd. If anyone knows how to work a dog it's Werner Rutsch and he's the one that shouldn't have any issues at all to speak english. Here is the info about the Club
Also, let me know if you need help with finding a good breeder if you are looking for a working line pup I can suggest a couple of breeders that are trustworthy. You may have to drive a couple of hours but they are small an great breeders that really take interest in their clients.