Unfortunately, this isn't necessarily very concrete advice, but have you read Tipping Point by Malcolm Gladwell? There's a lot of stuff in there about how things go viral, or how something becomes an epidemic. That said, it doesn't necessarily leave you with a lot of "do exactly this and it'll work" type of stuff, but it is a very interesting read.

Also, I need to read Haunted. I will do so soon!

Love ya!
Morgan