I've figured out Databus and how to solve your problem.
At the Databus site, select the file you want to make public. Then click the make public button. Then select the file again and under the options to the far right click the blue ball. Which will bring you to the create links page. There you will see the Direct link, Html link, Embed tag
Use the embed tag. You will only be using part of this line starting from src= and ending at .mp3
Put the address of the file in between the RED on your email starting after src= and ending before volume>
It should look something like this:
I dont know what the letter z is, but make sure if its the same as yours you are ok, if not, change the letter to what is in the line. Make sure the are in there.
I tried it out in my Microsoft Frontpage and it worked for me. Good Luck!