There are several ways that you can log data (it's not related to Arduino at all). Search around for how to log data in LabVIEW. Also, you can look in the the help documenation provided with LabVIEW. If you look in the "File I/O" palette, you'll see some of the different methods to use. One simple method for beginners is the "Write to Measurement File" express VI. When you use this VI, you will get a dialog that will allow you to configure the various settings for how data is being logged.
