If you are looking for business contacts in Germany, there is a very large database of them at Xing (formerly openBC).
At Xing you can present yourself and look for other contacts that you already know or for people looking for your skills.
On the basis that everyone knows everyone else withing maximum 6 hops, you will be shown how people you know already have contact with the people you are find.
Xing is available in a free version and also a premium version, which gives your more search options, easier communication and special offers.
To try it out: click here!
