The Chicago Tribune has posted the portions of the wiretap recordings released for use during the impeachment trial, and the transcripts. They are short - all four of the clips and the speakers explanations total just a little over seven minutes, but listen if you like. Chicago Breaking News also has a widget to play the audio. It is on this page, below the photo (which is worth a thousand words, by the way). More at Clout Street.
See the Criminal Complaint for more wiretap transcripts.