Tracking device for Bikes

Hi everyone!

last month someone stole my bike and now I'm planning to buy a new one (700-800$) and I don't want to lose it again so I'm thinking of making a tracking device to hide in my bike.
I don't know where to start and I'd like to know if someones has any idea or this has been made before... I could use any help

This is how I'm thinking it should work: it should be a little device with a long battery life (1 month more or less) and it should be placed inside the bike somewhere. Then when someone stole the bike I should be able to send a message using my phone or computer to the device and the device should return the location using google maps or whatever.

Thanks for the time! Any ideas are welcome

pd: and sorry for my bad english hahahaha

Here in Vancouver, BC we have a "Bike-Bait" program, that tracks stolen bikes via GPS, so these devices are available. Go to Google, police, high-end bike shops for info? E