Do you already have an Ipod? Then all you need is either and old stereo or boombox and an adapter. You can just put a TON of music on the ipod and even create pinball playlists for guest to choose from. As long as you already have an ipod that could be used, everything else would be on the cheap. And they make adapters for anything, so no matter the set up, there is a way to hook up your mp3 player.

I would highly recommend an audio streaming device called a Squeezebox. I have them all over my house, and they are fantastic! There are many different models, but you should be able to pick up one of the older ones fairly cheaply on eBay. I would recommend one of the V3 models that look like this:

Squeezebox.jpg

The Squeezebox will let you listen to your local music library, Rhapsody, Slacker, Pandora, etc ... You can also use it to stream pretty much any internet radio station including your local AM and FM stations. The coolest thing about the Squeezebox is that it can be easily controlled by some really slick apps from an iPad, iPhone, or Andriod device. When you combine it with a Rhapsody account, you basically have a jukebox that contains every song you can think of at you fingertips.

Man, you are retro. If you think about it, Mp3s have been around for over 10 years. Even they are a bit retro.