Hostels provide simple, budget accommodation primarily in shared rooms. They are good places to get to know other travellers. In Germany, as in many countries, two flavors exist: international youth hostels and independent hostels.
International Youth Hostels "Jugendherbergen" are owned and run by the association "Deutsches Jugendherbergswerk" DJH, which is part of the Hostelling International HI network. There are more than 600 hostels spread all over Germany in big and small cities as well as in the country side. Not only individual travellers are guests but also school classes and other youth groups. To sleep there, you have to be or become a member in a youth hostel organisation belonging the HI network (http://www.hihostels.com). Detailed information about this and each of their hostels can be found on the DJH's (http://www.jugendherberge...). Generally, this entails simply filling out a card and payng a few extra Euro per night. In general, the advantage of these places is that they tend to serve a buffet style breakfast for no additional charge, though this is not an absolute rule. However, the quality is often below that of private hostels although they are more expensive in germany, and many do not provide a good opportunity for socializing.
Privately run independent hostels are starting to be an attractive alternative for a similar price. More than 60 already exist in Germany, getting more and more every year. They are located in bigger cities, especially in Berlin, Munich, Dresden, and Hamburg. Only few are in the country side. Sometimes run by former travellers, hostels refrain from having strict rules. Especially small ones are frequently places where you can feel at home. Many are known for their vibrant, party atmosphere and can be an excellent way to meet other travelers. There is no need to be a member in some organisation to sleep there. About half of the hostels have organized themselves in a "Backpacker Network Germany" (http://www.german-hostels.de), which provides a list of their members hostels. A website which lists almost every independent hostel in Germany is Gomio (http://www.gomio.com/). Of course, international room booking agencies such as Hostelsclub, Hostelworld and Hostelbookers are also good resources, and give travelers the ability to leave reviews.
Many places, such as spa towns, but also cities like Berlin, charge a tax from generally anyone visiting overnight. Those taxes are usually collected by the hotels, B&Bs, hostels, and the like. At some places, in particular at spa towns, a tax receipt is handed over to the guest at check-in, which he or she will have to carry with him or her at all times that he or she is using some public facilities, as, for example, recreational parks, beaches, or even beach promemades. On the other hand, showing such passes often leads to discounts at some local venues. In some cases, passes from one municipality are also accepted in neighbouring municipalities.
At many places, e.g. Berlin, business visitors are exempt from paying the city tax. For using such exemption, it is required to hand over at check-in at the hotel or other place of accomodation an informal declaration issued by the visitor's employer stating that the stay is a business visit. Such declaration must then include the name of the hotel guest, the period of stay, and some broad indication of its purpose e.g. "business negotiations". As the rules for such letters vary from state to state or even within the state, hotels etc. will usually be ready to assist and provide some model letters.
Most international hotel chains have franchises in the major German cities, and a large variety of local hotels exist. All hotels in Germany are ranked by stars 1 to 5 stars. The rankings are made independently under consideration of strict guidelines and are therefore reliable albeit somewhat technocratic. The rate always includes VAT, is usually per room and includes in most places breakfast. Prices vary significantly by city Munich and Frankfurt are most expensive. A cheap and convenient way to stay are Ibis Hotels (http://www.ibishotel.com) and City Hotels (http://www.hotels-frankfu...), usually located near major railway stations. For people who travel by car, Etap (http://www.etaphotel.com/...) hotels located at the outskirts of cities near autobahns offer rates that can compete with hostel prices; though those hotels are not necessarily better and they lack the individuality hostels are renowned for.
There are countless campsites in Germany. They vary significantly in the infrastructure and standard. The ADAC, the German automobile club, offers an excellent guide for most German camping groups. If you are member of your national motorclub assistance and guides are free or at substantial reduced prices.
Some travellers just put up their tents somewhere in the country side. In Germany this is illegal, unless you have the landowner's permission. Practically however nobody cares as long as you are discreet, stay for one night only and take your trash with you. Be aware of hunting ranges and military practise grounds or you could be in significant danger of being shot.