Hi Torstern,
You could start off with using
DAQ Assistant to build your first acquisition VI
Once you get going, I would suggest you to start using the DAQmx acquisition VI's given in Examples shipped with LabVIEW
LabVIEW>>Find Examples>>Hardware Input Output>>DAQmx>>Analog Measurements>>Voltage Folder will have the required examples.
You could read each VI's Documentation to understand how it works and how to connect signals