Buying a house that is not on the MKT

Say there is a house you really like and would like to purchase or start a convo with the owners. What is the best way?

I feel like I a weirdo dropping a letter in the mailbox but going to shoot my shot.

I feel like if you texted or called they would think you are a scammer or something.

Anyone done this before with any luck. I’m imagining them reading my letter and putting it straight in the trash.