I lived in Holzminden,not so far from Paderborn,in the wesertal most roads are great for riding thereabouts,and places to visit would be HAMLYN,BODENWERDER,(Baron Von Munchausen ),The Hartz ,a must is GOSLAR,FAMOUS WITCH TOWN,and also Rommels HQ for a while.Berlin is not a good day trip,a long weekend is better. Charlottenburg to Alexanderplatz is full of interest.If you feel like a good ride,go down to DRESDEN,another long weekewnds worth.The most beautiful city in Germany,from ther is a boat ride thru the Sachischer alpes.And only a short trip over the border to Prague,another beautiful old city.I'm sure you will enjoy the trip,Germany is a wonderfull country,and the people very hospitable and friendly(away from where the allies bases are)
Campsites are plenty,and very well equiped.If hotel type accomodation is what you want,look for "pensions"(like a B&B) OR JUNGENDHERBERGs (hostels)Theres a great one in MELLE,not to far from Bielefelt,and on the same road to the A2.There are very many great places to see all over Germany,you wont be disappointed no matter where you go.