The Hot Club of Cowtown is at the Iron Horse, swinging and twanging and doing their thing tonight. They’re celebrating their 20th anniversary by releasing their first-ever CD format of their very first recording, Western Clambake. Western Clambake has only been available on cassette tape. You may now party like it’s not 1999. You’re welcome. Here’s what folks in the know say about Hot Club of Cowtown: Their music is like setting up camp “at that crossroads where country meets jazz and chases the blues away” (The Independent), and “remaining ‘conscious always that above all else, the music is for dancing and an old-fashioned good time’” (New York Times). The Iron Horse, 20 Center St., Northampton.