Paul Bradshaw posted an extremely useful tutorial today on his fabulous onlinejournalismblog.com.
Twitter has a "search within lists" feature that allows journalists to find local reaction to breaking national news ... meaning potential "sources" for stories about your "incident." You can use it, too.
Instead of paying high-dollar marketing firms to ferret out online chatter about your reputation, try this before you get into crisis mode. You might find it useful for identifying and trying to engage with stakeholders before they become credible sources.