Registering your arrival :
Germany
Registering your arrival
One of the first things you MUST do when arriving in Germany is register with the police. You must do this in your first week in the country if you plan to stay for more than three months. To get your "polizeiliche Anmeldebestätigung" you must visit your local registration office "Einwohnermeldeamt/Meldestelle" which can usually be found as part of your local town hall "Rathause" or police station.
There are many things you can not do in Germany without this document. Eg, set up a bank account, get a mobile phone etc. and failure to comply with this law could result in a fine.
It is also essential to remember to notify them if you change your address at any time.
Further information on both registering with the police and for residency can be found:
Expatica - Registration in Germany
Like in most European Countries, you no longer need a residence permit "Aufenthaltserlaubnis" if you are an EU citizen. If you plan on staying for some time, you can apply for a "Freizügigkeitsbescheinigung " after 3 months, however this is not necessary. This is your permission to stay indefinately. To get one of these you must prove proof of job eg your work contract (or a way of supporting yourself with approx 600€ a month) and that you have your own health insurance. There is no fee for this and it's granted almost automatically. This can be applied for at your local Meldestelle.