lol here is a better explanation for YouTube video embedding:
But it works poorly because YouTube blocks some/most songs on Aeria's websites.
The autoplayer I linked you to is more recommended. I thought it was self explanatory, but I guess I'll give you step-by-step instructions.
1. Go to Drop Box (https://www.dropbox.com/)
2. Save your MP3 file to your Drop Box
3. Take the direct MP3 URL, and place it in the URL area on http://www.sheepproductions.com/billy/
4. On the box next to it, type the title
5. Hit generate code
6. Copy and paste the code to your profile
Edit: the buffer time shouldn't be long (5 seconds max) It is probably because you didn't use the direct .mp3 url
So make sure the URL you put into the box ends in .mp3