Best websites for data?

[Kurosh Dejgosha]

I'm having a hard time finding good websites for gathering data. What do you guys recommend as a site for easily accessible historical sales data and current prices for sale? I'm trying to see trends in neighborhoods over time. All the big sites Zillow, Redfin, etc seem to be trash for this purpose.

What about looking up property owners? Is there a go to site for that? I usually google the guy's name and see what I can find there.

Property records? I use my local (Chicago) recorder's office website, but I can't download the entire database. I would really like to be able to search for specific criteria.