What is the output of your sensor?
If is is an analog signal in the +/-10V range or less, just wire it into an AI channel (differentail is usually good) . Try prototyping in max to validate oprtation and scale. next start with some of the AI examples that ship with LabView.
More detail about the signal is helpful.
Are you past setting up the hardware? Can you read in values in MAX? The next step would be to create Daqmx task, you can find examples on how to create an AI task in the LabVIEW example finder: Help >> Find Examples. Another option is to use the Daq Assistant in LabVIEW. This is an express VI whose setup looks just like a DAQmx task in MAX.
Unlike Paul wrote, I would suggest to use RSE instead of Differential, as the photodiode is not grounded. Otherwise you will pick up massive (sometimes above input limits) power line signal.