The best investments you can make are in yourself- learn a language, read a book and the newspaper, pick up hobbies where you meet others and can start networking.

Learn what newspapers publish what and when.  

I have started a Craigslist ad campaign and the Local newspaper Real Estate classifieds and I almost closed a deal but it eventually fell through.

Many investors are into their 40s, 50s, and 60s, and may not be too familiar with digital and social marketing opportunities, and may be limiting themselves substantially by only marketing their properties through "hard" methods (print newspapers, mailers, calls, etc.)I have a BA in Media Studies/ Communications, training in digital video production and post production, and experience in digital marketing through email, Facebook, and other social media. 

You can also find a starter via California Newspaper Service Bureau or Bond Services (rep is Bruce Sussin). 

The first two are published in your local newspaper.

Appraisers, auctioneers, fire truck chaser, neighborhood watch, craiglist ads, newspaper ads, these are all free ideas.

I'm getting mine from the local newspaper.

Craigslist, MLS, zillow, FSBO sites, street signs, newspapers, backpage....Find some investors that will give you their preferences and start analyzing the data.

Are the probates something that is only published in the newspapers classifieds?