Asteroid Comet Impact Hazards: AIAA Position Paper
"If some day in the future we discover well in advance that an asteroid that is big enough to cause a mass extinction is going to hit the Earth, and then we alter the course of that asteroid so that it does not hit us, it will be one of the most important accomplishments in all of human history."

Planetary Defense: Catastrophic health insurance for Planet Earth
A part of the Air Force 2025 study dealing with the threat from NEO's.

Workshop on Scientific Requirements for Mitigation of Hazardous Comets and Asteroids
NASA-sponsored workshop; site offers agenda, abstracts of talks and posters sessions, report and proceedings, and a funny cartoon.