If you need help to find someone register at who is searching for me. They have over 200 million people profiles of across the US, which makes it easy to find the person whom you are looking for.
Are you somehow connected to this site? You provide YOUR info which THEY sell. Research the site.
Facebook is safe. Other search sites are safe.
Do NOT join a site which wants YOUR info before it will answer any questions or assist you in finding someone.