Tiempo total de reproducción en iTunes por artista

Puedes hacerlo con AppleScript (suponiendo que estés en un Mac). Aquí hay un código que he creado. Abre el editor de AppleScript, pega esto y ejecútalo.

set dialog_reply to display dialog "Enter artist name:" default answer "Boards Of Canada"

if text returned of dialog_reply is not "" then
    set plays_list to {}
    set times_list to {}
    set artist_name to text returned of dialog_reply
    tell application "iTunes"
        try
            tell source 1
                tell library playlist 1
                    tell (every track whose artist is artist_name)
                        set plays_list to played count
                        set times_list to time
                    end tell
                end tell
            end tell
        on error
            display alert "Couldn't find anything by " & artist_name as warning
        end try
    end tell

    if length of plays_list is greater than 0 then
        set total_time_minutes to 0
        set total_time_seconds to 0
        repeat with i from 1 to (length of times_list)
            set this_time to (item i of times_list)
            set text item delimiters to ":"
            set time_elements to every text item of this_time
            set this_minutes to item 1 of time_elements
            set this_seconds to item 2 of time_elements
            if item i of plays_list is greater than 0 then
                set total_time_minutes to total_time_minutes + (this_minutes)
                set total_time_seconds to total_time_seconds + (this_seconds)
            end if
        end repeat

        set total_time_minutes to total_time_minutes + (total_time_seconds div 60)
        set total_time_seconds to (total_time_seconds mod 60)

        if total_time_minutes is greater than 0 or total_time_seconds is greater than 0 then
            if length of (total_time_seconds as string) is less than 2 then set total_time_seconds to "0" & total_time_seconds as string
            display alert "You've played " & artist_name & " for " & total_time_minutes & "m " & total_time_seconds & "s." as informational
        else
            display alert "Looks like you haven't played anything by " & artist_name & " yet?" as warning
        end if

    end if
end if

Hay una aplicación en la Mac App Store llamada mySpins que te da todo tipo de información como esa: recuento de jugadas, tiempo total de juego, etc.