Welcome to the Louisville Restaurants Forum, a civil place for the intelligent discussion of the local restaurant scene and just about any other topic related to food and drink in and around Louisville.
Here's one website that some of the bigger ones use: http://foodtrucksinlou.blogspot.com/ just click on the event calendar and you can see what day they will be where. Robin also has a Twitter site where most of them Tweet to with information: https://twitter.com/RobinGarr/lists/hotbytesfoodtrucks. Other than that you just need to find their listings on either Facebook or Twitter to see where they are at any given time.