While an IP address is what allows e-mail and such to find a particular person, it is generally not identifiable after the fact to a particular person or home address.
Unless you have your own web page with a fixed IP address, it's assigned to you when you log in and can change over time. The first set of numbers will indicate general physical location. Now with wi-fi routers and such that are permanently connected, it might remain the same until you reboot your router (not 100% sure on that). Also note that a person can be using a work computer or library computer, and the IP address would point only to that business. I wouldn't worry too much about hiding someone's IP address, but also not real helpful to spread it around.