Then I paid $25 to some online background check agency to find out if the owner had any other liens/bankruptcies/judgments against them and also got their contact info from there.

You can also check meetup.com or search Facebook for real estate investment groups, clubs, or meetings in your area.I'm in a small town where networking is impossible, so I do it online through facebook groups and BiggerPockets.

So many people out there ,  that have online courses.

And once the houses are up, are prices going to come down as new units come online but homebuyers pool increases continuously while they all have $25k?

There are a lot of online sources out there versus going to the local courthouse.   

.-- All the info you need is available online from the local assessor, and pay attention to what the local community has tacked on to the mill rate.

In the old days, I would advertise in the Fresno Bee, and in the local freebee advertising rag.Nowadays, everything seems to be going online. 

Courses online are relatively cheap and there's some brokerages like kw that have offered free online courses with no obligation to join afterwards.

From time to time we also hold an online meeting for talking about a specific topic.    

If the owner is an LLC, you can try to check online Corporate records to see who the agent for the LCL is and their address.