But is there a way to do it in dreamweaver? It seems as if there should be...
If you don't have Flash, You should look online for FREE or reasonably priced Flash Slide Shows. There are dozens of them, and some can play audio while showing a picture.
Otherwise, if you do have Flash, someone on the Flash forums could probobaly give you a couple lines of action script code or a quick flash tutuorial and you will be done in no time.
So to answer you question. You can't embed audio into an image with DreamWeaver, or any other HTML editor for that matter. Your best option is to use Flash.