The Adsense Coder Plugin let you put your Adsense code where you want within your blog post. Unfortunately you have to switch to the HTML View (Shift + F11) and put your code outside of a paragraph tag (<p>….</p>) to avoid conflicts with the paragraph which the plugin creates.

Download: Adsense Coder plugin

• Insert MP3 Player
  The Insert Mp3 player plugin will let you add a small MP3 Player to your blog post. Options include, Let vistors Download MP3, set Width & Height of MP3 Player, Center Player in blog Post, ......