How can I determine my IP address?

The Public IP address can be used to ascertain a location, but it is not a location in and of itself.. That location is somewhat general as its based on what your ISP reports and in most cases it will be the location of their regional internet hub somewhere "near" you. Its been know to be off by many many miles from one's actual location. Sometimes in a different city or even state. So it's not really useful for the locating of someone.

The Public IP address is generally not tied to you in any specific way and most ISPs hand these dynamically so while you may have one now it can be a completely different one tomorrow or 2 days from now depending on how often your router refreshes the connection to your ISP.

On what device or computer are you trying to determine this? This will dictate the steps you need to follow.

Also, do you want the public IP address issues by your ISP, or the private IP address you get for the local network you are connected to?