First and foremost, whether his threats are true or not, they are in fact illegal. If you have already told him to leave you alone, you NEED to stop contacting him through forums and you need to leave him be. The more you continue to respond to his idle threats, the harder it will be for you in a court of law. You need to print anything and everything that you have to/from him. This includes any and all forum replies. If any topic on any of the forums get deleted, you still have proof that they existed and they are permitted in court.
Now, again, what he is doing is illegal. He is slandering your name, he is threatening (indirectly) your children. Posting all your personal information (name, addy, email, phone, DL, etc.) IS illegal...
Taking pictures of your children IS illegal so long as they are under the age of 18 and or still under your sole guardianship. If he has any pictures of you and or your family, and he choses to post them on any website without your consent it is illegal under the federal privacy acts.
His threats are actually a federal offense at this point. They would be known as terrorist threats and he can spend many, many years in a federal prison if he keeps it up.
You NEED to get a restraining order against him and file harassment charges. If he so chooses to go against those charges, he will be picked up and put in jail.
The fact that he keeps telling you he will see you on this day or that day can also land him in jail. That would be stalking. Again, another charge that would stick as it is certainly pre-meditated since he has already stated it on several topics.
I'm sorry to say but it seems as though you are dealing with someone who is much more than bi-polar. You seem to have a true psycho on your hands. When you are dealing with a person like this, you want to always assume that they will follow through with their threats. He may not, in fact, he probably doesn't have enough balls to do so, but you need to be prepared in case the situation does arise.
Mr. Sloan seems like the true definition of a coward.