3. google it here's an example for you
http://www.lawdepot.com/contracts/cease-and-desist-letter/?loc=CA
2. They can still mail you if you don't request they take you to court, but who cares about mail just rip it up.
1. You got it if youre specific and make that request
4. I,d register it, that way you get a signature and they cannot deny receiving
Pretty sure I'm correct in my reply but maybe others will confirm.
Good Luck