Massad has written an article for Backwoods Home, entitled "Terrorism in America, the Armed Citizen's View": http://www.backwoodshome.com/articles2/ayoob150.html
I find this quote rather interesting, wondering if there should be more training in disarming techniques for the CCW citizen?
Hand-to-hand combat, by definition, only works at hand-to-hand distance. Trying to punch, kick, or throw human monsters armed with guns does not have a great history of success, so your best bet is to effectively learn disarming. Properly taught, this will be a structured system that attacks the weapon rather than the man holding it, using your initial movement to deflect the gun barrel away from you (or another intended victim) and then flowing into a leverage-based movement pattern that rips the weapon out of the malefactor's hands.
At Massad Ayoob Group LLC, we teach a system based on the work of Jim Lindell, in my opinion the leading expert on disarming and on gun retention, which is defeating a Bad Guy's attempt to disarm the Good Guy. In the Pacific Northwest, Firearms Academy of Seattle also teaches this to qualified private citizens; such systems are normally taught only to police. Few conventional martial arts dojos have anything this effective, so for local training your best bet is to seek out a Krav Maga school. It has been my experience that most, if not all, Krav Maga instructors will teach very effective leverage-based gun disarming.