There are tons of food trucks in Las Vegas, some itinerant and some with usually fixed locations. I'm not aware of any ON the strip. Lots of info about specific ones on Yelp, with links to individual trucks' websites that have info about where they are located: http://www.yelp.com/search?find_desc=Food+Trucks&find_loc=Las+Vegas%2C+NV
There are sites that attempt to track the whereabouts of food trucks in real time. Some of them are sketchy both in quantity and quality and clearly attempts to garner advertising. Here's one of the better ones: http://roaminghunger.com/lv/vendors/m...