I think the main reason they aren't available now is because there aren't enough of the systems in use to create a demand worthy of the cost of obtaining the protocols. Perhaps they will be available someday...
Shawn, I was going to try and purchase an LTR radio on ebay and program the frequencies and talk groups and ID's into them myself. I am NO technician so I would pay someone to do it. I wonder if anyone else has tried this and what were the results?