JoinTogether.org continues to be an unending font of material for me. In this piece they report that More Newspapers Banning Gun Classifieds. This happened here in Tucson a couple of years ago. The result? UsedGunsTucson.com (currently defunct as of 2017), a web-based classified system for people buying and selling their firearms privately. At no cost, mind you. This guy runs the site on his own dime. And I’ve used it. It works quite well.
I hope others establish sites like this to replace their newspaper classifieds.