How to access GPS location without internet
If you want to send data to a server on the internet, you will need an internet connection, or at least a connection to a internet gateway.
Which type of connection you use, and how you set up that connection, depends on distance, speed, and coverage you need.
Probably the most universal for your application, in the sense that it will work wherever a phone would work, is to use a GSM/GPS module with an Arduino. You can google around for such modules; there are many. Note that you will need a SIM card for every module you use.
The GSM-bit of the module can then be used as a modem to communicate with your server over TCP/IP. There are many examples showing how to do that on the interwebs, so I won't go there.
If this doesn't help you enough, please add more detail to your question and I will edit the answer.