I don't know about this person, but my name is pretty unique

Enter it into Google and my (former) home number is a click away. And it's only former because I don't have a home phone anymore

There are services that round up all this information and link it that I'm sure sales people would use as well

Yes, there are companies who sell their app which is just a database of contact information and a plugin to link it,

Who knows where those companies got it, but you can sleep soundly knowing you bought it from a “Real company.”

I am pretty sure they are getting it from linkedin. I felt like a conspiracy theorist but I signed myself up for a SIP line and started getting calls on it from Datadog and The Register after I added it to linkedin.