Problem with that script NanaFreak is that it probably only notifies you from that point onwards and not any before that, which in one way defeats the purpose but in another it's still doing it's job as it should. And from what I gather the user wants one about contacts before, which as far as I know can't be done anyway (will stand corrected on that part).
As for seeing who has blocked you = not possible. No ifs not buts no nothing...and just so you can read about it have a look
here
Hope this helps in some way.