Unfortunately, the truth of the matter is that so called free online reverse cell phone directories are not able to provide you with the results you really need. If you have never had to deal with someone harassing you and your family, you may not think much about ways to find out who it might be.
You can try to track down the contact details of the person for free, or you can take the fast and easy way and pay a small fee to retrieve his or her cell phone records. It use to be that you would get a strange hang up or midnight caller only at home, but now even cell phone users are getting these kinds of problems. Have you ever received a call and the caller-ID only tells you the number but not the name of the person who called?
The listing will also tell you if the number is a landline, and even what phone company they have, though this information is not always accurate and up to date. This may give you the best results, but you can try many more different reverse lookup services as well. That means an unknown number from a different country does not have to remain a mystery.
So, do yourself a favour and appreciate that there's no such thing as a free reverse cell phone look up. Don't be afraid to take advantage of what is out there.