I just watched "Coral Reef Adventure"
http://www.coralfilm.com/and in the credits it listed this site.
http://www.reefcheck.org/
"According to the United Nations’ Global Coral Reef Monitoring Network, 10% of the world’s reefs have died in the past 4 years, and nearly a quarter are sick and suffering. More than half of the remaining reefs are seriously threatened, and scientists estimate that if today’s trends continue, corals may vanish entirely within the next 40 years."
This is a good site as well. Every day you click the link and it saves 7.4 square feet of reef.
http://rainforest.care2.com/