There are ways to identify telephone numbers for free. Rather than make a call to find out who is on the other end of a number you don't recognise, you can search online to find out who the number belongs to.
Go to the White Pages online. Input the telephone number in the form labelled "Reverse Phone," and then click "Find." The search results may include the name of the person or business the phone is registered to and the address of the person connected to the phone.
Go to the Yellow Pages website. The Yellow Pages lists the telephone numbers and addresses of businesses. At the Yellow Pages website, click on the "By Phone Number," option and then enter the number, next click on "Find." The search results can give you the name and location of the business attached to the number.
Conduct a general Internet search. Enter the telephone number in a search engine like Google, Yahoo or Bing. If that particular telephone number is listed on a website, it should come up in the results of your search. Match the number with the name of the business or person identified on the website.