Why is it so hard to find literature about the 5-18-80 Kwangju macre?

I've looked hard and only found one book called "Kwangju Diary". At $133 for a 170 page used paperback, it has to be one of the most rare Korean history books around. I know the Korean Govt burned a lot of copies and the US is embared because they OK'ed the release of DMZ Korean border troops to put down the rebellion against Chun's dictatorship, but can info be THAT hard to come by? We were in Mokpo to escape the riots in Seoul and when martial law was declaired. Only nearby Kwangju refused to stop demonstrating. The ROK army came down on the students so hard almost a million common citizens joined them and kicked the police and troops out. They set up their own government and crime rates dropped to zero. The elected their own leaders and suddenly were attacked by paratroopers and tanks. Still the students kicked them out, siezing arsenals and cars as the death toll climbed. Finally me and my wife walked out of the surrounded province as the fighting spread to Mokpo.