If you go to your tools menu, you will find Instrumentation>Find Instrument Drivers. You can start your search with this or just go straight to the Instrument Driver Network and do the search from there. You will find a driver listed there and the driver page will take you to Keithley's web site. Search there and you will find an IVI driver they wrote for the 6487.
There are no drivers for the Keithley 6487 picoammeter. You might find some for the keithley 6485 that use IVI-based commands, but the last time I looked, the LabVIEW driver finder can't find them either.
