package main

import "fmt"
import "os/exec"

func main() {
    fmt.Println("Ding!")
    cmd := exec.Command("paplay", "/usr/share/sounds/freedesktop/stereo/complete.oga")
    cmd.Start()
}

package main

import "fmt"

func main() {
    fmt.Println("Ding!")
}

--- 
+++ 
@@ -1,7 +1,10 @@
 package main
 
 import "fmt"
+import "os/exec"
 
 func main() {
     fmt.Println("Ding!")
+    cmd := exec.Command("paplay", "/usr/share/sounds/freedesktop/stereo/complete.oga")
+    cmd.Start()
 }
Use os/exec and paplay to play sound
