Display icon in the post

Hi

i dont know how come my client had a weird idea.

well the question is how to display the icon beside the post in the sidebar.

i have two different kinds of post…

1) for the audio
2) for the video

so here for the audio i want to display the audio icon and same for the video i want to display the video icon.

can any one tell me how to do this task complete

thanks in advance

mahendra