I've been lurking on this thread for a bit, but I want to say I am so sorry to you, your family and friends. I pray they catch who is doing this.
Has the humane society been involved? I'm wondering if there are other animals or livestock that have been targeted as well and maybe just not horses.
I too feel that the media needs to get involved on this, I know there is a case and wouldn't want it to be jeopardized, but if I lived there I would WANT to know this is happening. Someone might be able to set surveillance cameras up on their property (the ones deer hunters use). Hmm, I just don't know I'm sure you guys must feel pretty helpless.
Again, I am sorry and my prayers go out to all of you.