My best advice would be to find someone who lights REALLY WELL (on a movie set, television show, commercial production house, or whatever)… and pester him or her until they are willing to let you just hang around and watch for a few days or so (maybe offer to assist or work as a gopher for free).
Before I was a wanna-be movie director, I was a wanna-be actor. Even though I thought I knew a fair bit about it, I learned more about real lighting my first day as an actor on a real set than I have in all the other classes, books, and tutorials put together. Watch everything they do, and for each thing they do, ask yourself “Why?” (It’s probably best not to ask the DP or gaffer that question TOO often, or you’ll get booted from the set).
I worked for a while as an actor on a network primetime show where the DP was this horrid horrid French guy who CLAIMED not to speak any English (although he could). He was an evil, nasty man, treated his men like crap, was abusive to everyone from talent to crew (basically everyone but the director). He was basically just a horrible person… but the things this guy could do with just one instrument and 5 feet of gaffer tape was amazing. I tried to learn as much as I could just by watching him work…. but stayed out of his way!
Todd