It is true that someone can ping your computer to acquire your IP address. However, for most people, it doesn't go much further than that. Unless you purchased your own domain and registered your IP address, you'll generally be seeing your ISP's icontact information. Typically it will include your ISP's name, the range of IP addresses they own, and their contact information. Sometimes it will also include the closest major (or mid-sized) city where their servers are. In this case, a person could narrow you down to an X-mile radius from, say, Seattle, Washington. However, they can not find out your personal information (name, address, phone number, etc) unless they either hack your computer (assuming such informatio is on your computer) or your ISP's database.
On the other hand, if you did register your domain/IP address, you're contact information is probably available by typing in your IP address or website into a domain database. In either case, you can see the information for yourself by click here to see your IP address, then searching for it using CheckDomain.
Hope this helps,
John
P.S. My advice would be to have your phone company trace the harassing phone calls, then change your number, preferable to one that is unpublished/restricted.
I've been receiving harassing phone calls. I've been told that someone can "ping" my computer to get my IP address, then use that information to gather all my personal information. Is this possible? I have a cable modem, so my IP address is always the same. I've already notified my ISP and the phone company. Thanks.

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