Douglas Niedt has a summer individual master class in Kansas City, Missouri, United States. You are the only student from 3-5 days, and you are given 3 one hour lessons every day. I did this in college, and I spent a week practicing, receiving lessons, eating, and sleeping. I felt like I hade gained a year of playing experience in the week that I was there! When you set it up, you send him a list of your repertoire, and he hammers technique, musicality, interpretation, and nuance. He even watched me play and slightly reshape my nails based on the attack that I gave the strings! I highly recommend this option. Now that I live close to Kansas City, I plan on studying with Doug over the summer.
Here's a link to his website with the info: http://douglasniedt.com/classicalguitar ... niedt.html