I would try the police again - different officer (or if you went to the police, call them out to your house). She could be charged with stalking, harassing communications, perhaps even terroristic threats. Get a copy of your cell phone bill with all of the communications to make it easy for them.
(If they still won't take charges, perhaps contact the district attorney's office - family violence division - and see if they can help you out directly.)
The other thing I can think of is to try to get a restraining order from your local justice of the peace. This does not have much bite if there is a violation.
Talk to the Justice of the Peace about getting a peace bond. If it is specific as to her actions, and she violates it, the police will respond. You can also retain an attorney to get a restraining order against her, that if violated, will lead to contempt of court.
First, don't worry about the fraud threat - even if it was valid, there is a four year statute of limitations on fraud. I agree that you should try the police again - if they still won't help, then you have a claim against your ex for trespass, intentional infliction of emotional distress, invasion of privacy, etc. A civil court could issue a Protective Order against her (& she can go to jail if she violates it) if the judge is convinced of your facts. You'd need to document the effect on your business efforts a/w/a the emotional distress, so that the court understands the results of your ex's actions against you.