Are you only looking for trucks? If not there are a couple of places that do good tacos near the airport. LAX Tacos and Taco Express (which actually shares space with the Arco gas station on the corner of Arbor Vitae and Aviation) are both chow worthy.
543 W Arbor Vitae St
Inglewood, CA 90301
9200 Aviation Blvd
Los Angeles, CA 90045
Seeing as you're not getting a whole lot of replies, I'll weigh in. I've eaten at a couple of trucks (once) about 2 years ago. The Tacos El Comal truck that parks near the Lennox Market on Inglewood Avenue. http://www.greattacohunt.com/2010/09/... The other truck was on Hawthorne Boulevard by the El Rancho Market. Neither was that good, but I only got about 3 tacos per truck. There is another a few blocks north (opposite Don Rogelio's restaurant) on Inglewood Avenue called Taco Dollar. Back on Hawthorne a little north of El Rancho Market is another vendor whose name escapes me. I haven't tried the last two. I wouldn't recommend the two I tried and I can't say on the two I haven't tried. Sorry not much help here, I'm afraid.