Here are some resources for people who have taken the “Play Piano Despite Years of Lessons” course or watched the video on playing piano by ear:
Watch the video here.
I hope that helps you a lot. Get some lead sheet music with the chords, and start applying some of this. It really works. I’ve seen people take this information in 15-20 minutes and learn how to play by ear amazingly fast. This will take practice, of course, but it can be fun practice.
Let me know if it’s helpful, or if you would like more instruction on this topic.