https://missouri.phonenumbers.org/
There are some other methods for obtaining phone numbers, such as reverse searches and public records requests, but these may require fees or charges to access ...

https://play.google.com/store/apps/details?id=com.skiily.www.phonereveal&hl=en_US
Perform reverse phone number lookups to figure out who is calling you! Enter a phone number, and the app will attempt to lookup the name.

https://www.justanswer.com/cell-phones/5x9hd-reverse-phone-lookup-information-not-free-cost.html
The reason it costs money is because unlike land line companies who sell your phone number to public companies as soon as you sign up for ...