Here’s another collection of found audio recordings (this one you have to pay for), as compiled by musician Jacob Smigel

Eavesdrop: a wealth of found sound is a collection of anonymous recordings found at thrift stores, yard sales, and in trash bins over the past four years. These unaltered tracks come from audio or micro-cassettes, 8-Tracks and home-recorded records. Many of the clips are segments from audio diaries, tape-letters, the sound of road trips, fights, crying, family moments, telephone conversations/messages, or the amusements of children or the mentally handicapped.

Sample mp3s:

Hamburger Hamlet

Trailer Couple