Start with a Simple Search on the Internet
You can try with a simple search on the Net. Type the cell number in the search bar of any search engine you prefer and see what it comes up with. In case you are looking for the cell number of a person, you need to type the name and as many details as you have. Do not worry if you have no details; just the name would do as fine. In most cases the cell number of the person would be listed for some reason of other such as networking site (informal), business sites, soft copy of CV, a list of participants of a workshop/ seminar/ training program/ conference, etc. There are so many places where people leave their cell numbers, even when it is otherwise unlisted.
Check out the more specialized sites. Run a search on the Internet for specialized sites, which compile cell phone numbers such as http://www.nonpublished.com. You will need to type keywords such as “free cell phone directory”, “free online cell phone index”, or such similar phrases which tell the web crawlers to find for you free cell phone directories.
Take the help of reverse lookup sites. There are another type of specialized sites, i.e. reverse lookup sites. Here, you have the cell number and they give you the name of the person. Therefore, this will work only if you have some cell number of the person you are trying to trace. Once you get some information, you could once again use this to further your investigation regarding the cell number you are presently seeking. For example, an old number would give a place of work, an address, etc. which you could once again place on the search bar to find further details.
Try volunteer directories
Type in the search engine “volunteer cell phone directory” and then shift selectively through the results. These directories consist of cell phones numbers, which are voluntarily fed into online directories. However, in case the person who number you are seeking did not list his or her phone number, you will not find it
Save time, pay fee. Though this is a “How to find cell phone numbers for free”, sometimes, it is better paying a small fee and getting your results faster, than spending time and effort searching and searching and searching. Look for pay sites that charge low fees, such as US $20-30, which is often worth the trouble. Examples of such sites can be found in the resources category below. These sites find results you can expect before you part with the fee.