Live GPS tracking for personal buddy

hello
I need your help in my project
it's a live GPS tracking for personal buddy and specified for human buddy
so I want to make a device which will be with human and a control and tracking unit which will be with me to tracking and see where he going to.
also I need to know some info about who I'm tracking? let say I have 10 people and I want to know which one I'm tracking know ? so I need to storage a data for everyone.

some friends suggest to add some feature like you can integrate it with some circuit to show his Heartbeat,Temperature, ....etc

so I need your help to choose best way to make it
what I need ?
GPS transmitter ? does it available ? do I need permission from government?.....etc

thank you so much in advance