There are alot of places where such data can be sourced from. Despite searching for random people is not considered ethical due to privacy reasons but when it comes to Security and Forensics, this sometimes becomes a must (IN A GOOD WAY).
Adhering to the last statement of the previous para, one such example to searching people for a good reason is - "Police officers in various jurisdictions have power to search members of the public, for example, for weapons, drugs and stolen property.[1] This article concerns searches of members of the public who have not been arrested and who are not held in detention. For search powers in relation to those persons see Search on arrest and Searches in detention. For searches of property, rather than people, see search and seizure."
WhitePages and TruePeopleSearch are one of the best in regard of searching people. These have a facility where one can go into these and ask/request to remove their respective Information/Personal Details, and they will remove it (This feature is mostly used by those who want to keep their tracks covered completely).
WhitePages might have different extensions for different countries. "whitepages.com" is the US extension.
LINKS
WhitePages - https://www.whitepages.com/
TruePeopleSearch - https://www.truepeoplesearch.com/
FastPeopleSearch - https://www.fastpeoplesearch.com/
FastBackgroundCheck - https://www.fastbackgroundcheck.com/
WebMii - https://webmii.com/
PeekYou - https://peekyou.com/
411 - https://www.411.com/
Spokeo - https://www.spokeo.com/
That's Them - https://thatsthem.com/ (Can be also used for phones, addresses, IP address, etc.)
Google - https://www.google.com/