What are the largest databases and more obscure sources of PII?

I recently had a falling out with a loose friend that apparently has more extensive people lookup abilities than I do, and after not really caring about my digital privacy for the majority of my life, I'd like to now remove as much of this information from the Internet as I can. It kind of sucks because I used to enjoy looking up what was available about me, but now I am seeing the downsides.

I've used google's tool to …

databases digital digital privacy information internet life people pii privacy remove