There are many many sites on the web that do offer free reverse phone look ups, but these only cater to landline phones. 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.
There are many more possibilities, but finding out whoever it is that's trying to call you can be extremely important, not to mention very, very revealing. But, can you remember when you were given your local telephone directory, it only contained information for a limited area. It seems that directory assistance itself needs some assistance sometimes.
However, the more information you can provide, the more concise the search, and the better the results. On another note, if you are not sure how much information is listed about you in the reverse white pages, you can perform a reverse phone lookup on your phone number to see what results are returned. Reverse look up of phone number will help you know the location and the identity of your nuisance caller.
Checking someone's name with phone number details is easy, especially if you are using one of the best reverse phone search products. If you really want to access such records then I believe paying a small fee is a price worth paying.