Does anyone know where I can find copies of real hate letters on the web? 10 points!?

Sorry if it sounds like a creepy question. I'm writing a story for a major school ignment, and I want to include a hate letter, although I've no idea how to writeone. I'm thinking one of those real mad ones, where the writer seems a bit deranged, like ones that cult members and such send... oh dear this does sound bad. If anyone knows of anywhere I can access some of these sorts of letters, I'd be ever so grateful :)