About 15 years ago I helped put together a system consisting of a GPS transceiver kind of radio and a web site where you could track vehicles of any type.
This used a "private" set of gps satellites (yes there are more than one gps system up there martha).
We had them on Helicopters, C-130 aircraft, ships and sailboats, 40 foot tractor trailers (for FEMA), Lots of things. Project died due to lack of focus by the people in charge of "marketing".
It was pretty cool work, you could see in real time what & where & how fast and at what altitude your 'assets' were doing.
The devices were even capable of sending and receiving email and we had software that worked with MS Outlook.
Moral of story, doesn't matter how cool your project is - get paid upfront.
I should imagine there would be something out there for the general public by now.