I develop a self-hosted service designed to do exactly this! It's not quite finished yet, but it's at the point where enough functionality works that it can be used for testing.
https://github.com/connervieira/HealthBox
The docs/USAGE.md file gives an overview of how HealthBox works. Feel free to poke around in the other docs/ files as well.
I maintain a program called Assassin that has an ALPR camera database as a headlining feature. You install it on a low-power SBC (like a Raspberry Pi) in your car, and it notifies you before passing ALPR cameras (among other threats). I only personally maintain the database in my states, but I like to think it's fairly comprehensive.
With some technical experience, you can create a pretty elegant system with concealed status LEDs, configurable audio alerts, and more.