I'm really sorry if you took that wrong. I was in no way laughing at you. I think it sucks the situation you are in.
What I meant was funny is that Lufc and I where thinking the same thing.
Here is a link to a guy in Australia that can help you out.
EDIT: ooops sorry your in Austria, I dont know of anyone there.
Well here is a link to how to use a multimeter, maybe you will find it useful.
http://www.multimeterwarehouse.com/usingamultimeter.htm
If you have zero ohms you have a short. Or near to zero, some times the meter will measure the resistance in your leads. You can measure the resistance in your leads by simply touching them together, whatever the meter reads is your zero.