If someone has your IP address and your PC is vulnerable (not patched, not configured correctly, not protected with security software, not behind a firewall) they simply need to browse your files and look for personal information about you. If every possible avenue of intrusion is taken care of, you are 80% protected. Why only 80%? Because you can have all the techical gizmos in the world, it only takes one human mistake (like opening a trojan attachement in an email) to unleash the hounds.

It's like asking, "If someone knows where I live can they discover my name?" Are your doors and windows locked? Yes? Good. Is there any personal information in your garbage can on the curb? Yes? Well..... so much for the locks.....

Yes it is possible but EXTREMELY unlikely. Im talking high level government and hours of data harvesting. Someone would have to have plenty of resources and time to swim back up into your personal data. I wouldn't worry about it....unless you're Osama Bin Laden.

EDIt----- i forgot to add this, there are programs that you can download for free to alter your ip, mine currently says im in taiwan, i think. Look for one on nonags.com, they have a variety.

If
1) you're using your own account you've got with your ISP;
2a) you've given your ISP your real name and address;
and/or
2b) you dial in from your home phone;
3) haven't spoofed your IP address;
4) the law enforcement agency has a legal reason for
wanting the information from your ISP;

it's a simple matter. It doesn't matter if you've got a static IP address or a dynamically assigned one. Your ISP keeps a detailed log of who's connected when, and what IP address they had at the time. It's just a small, quick search in the database.

I have done this as a job. One of the more notable cases I had was where a kook was threatening our Department's minister. We got him! Turned out to be some harmless young fool.

Mind you, the average Joe Bloggs on the street can't (legally) obtain this information. If someone works in law enforcement and they have a legal reason to obtain the information, the ISP MUST comply.

If you're going through an HTTP proxy in some distant, hardly even heard of country (like outer Mongolia or Woop Woop) who is unlikely to comply with handing over their records (assuming they keep any), it becomes harder, but still not impossible. Nothing's impossible in the land of internetworking.

Another difficult situation is where the person you're trying to track down uses different Internet cafés, public libraries etc. to do their dirty work from.

Look at the guy who so called hacked Sarah Palins yahoo account. It took just a few days to track him down and he tried to hide is tracks using several
websites to mask your IP. The average person does
not have the resources or power to really find someone, but a real tech guy, maybe. The goverment, yes if they want you bad enough. Now this happens
to yahoo accounts allot, so I don't see why they
went after him, just because of her, that is wrong.
If they track him because of her, then they should
do it for everyone..

It is almost impossible to hide your tracks today, you must work alone, do your homework and be completely careful about everything, buy computers with cash, be competely mobile, etc.. Allot of prep work needed.

It is entirely possible. From the IP address you can determine the latitude and longitude of the persons connection (really only valid if they have a static IP). I'll leave the how of that to you, but it's a very simple process. *cough ip-adress.com cough* And it doesn't just show the ISP location either.

From there, google maps will show you a satellite image of the location, and a quick phone book search for the persons name in that location will turn up their physical address.

Done and done.

ONLY International Law Enforcement Agencies can get your exact location from your I.P. Address and they get it only if they can prove that the I.P. Address whose information they want was involved in illeagal activities. They can't just get information if they want it unless the Internet Service Provider is conviced that the I.P. address they're requesting has, in fact, been involved in illeagal activities.
However, you can get a NEARLY exact location of the user whose I.P. address is known by performing a reverse DNS Lookup or Traceroute. The location provided by this is almost always off the mark by a couple of miles but they will NEVER get all of your exact details by these methods.

you see ip address is your identity on the internet or the untrusted network and there is lot of chances that one can get to know lot abot you through it for example they can use a whois query to get to know you location for example in which country you are living,what is your ISP's name and basically if they will be able to hack into your ISP and get to their database forget about about they discovering your street address they can locate your house.

i personally recommend to use a good firewall and any other spyware detector and if so use a antivirus.

If you have a cable modem or router the Ip address changes everytime you power reset that device. So IP addresses can be constantly changing? The only real identifier back to your individual PC is through the MAC address which resides on your NIC(network interface card)card. So unless you change nic cards on a regular basis your mac address will stay the same. But then you have to ask yourself, why would anyone want to come and get you??

my ip with juno.com ISP says that I am in or around Fransisco, so I don't know as I am not near that location... my ip tho is dynamic and is a level 3 communications one...

I heard two years ago that the NSA and the FBI were looking into this.
If you have a fixed IP address, then they could certainly locate the network that you are on and contact the network administrator for a diagram of the layout of the network that could reveal your actual ohysical location.
If you are running DHCP, and have a temporary adsress assinged every time that you conect to the network, then this would make it more challanging for them. Remember too that every computer NIC card has a fixed MAC address that will identify the computer that you are on and that this address can be discovered over your network.