Change Post/Page Icon to Custom Logo?

Hey people,

Thanks again for all the help here, a great theme and amazing support for a newcomer!

My site: http://www.affm.net.au/wordpress/

I’m hoping to change the Post / Page icons to a custom image / logo.

I’ve read this snippet and it seems to indicate that you can change the icons BUT only to Entypo characters. Can my request be done? How?

Thanks so much!
Brendan