The National Trust for Historic Preservation's Tear Downs and McMansions Resource Guide
When a neighborhood becomes aware of the tear-down phenomenon happening close at hand, that's the time to organize a committee or community group that can help educate real estate agents, builders, and homeowners about the options that are available. The National Trust for Historic Preservation recently put together a "Teardowns and McMansions Resource Guide," which allows neighborhood organizations to learn from what other communities have done to stem the tide of tear-downs. Filled with useful information, tips, and strategies, it should be the starting point for anyone wanting to help preserve the character of their community.
Scott Evans documented the tear-down phenomenon in his own neighborhood on his blog.