The Hughes unit is available at some Best Buy locations. The Philips unit is largely unavailable. If you know of a Circuit City in a really small area, you may be able to get a hold of one. The Sony unit is $100 more expensive than the others, and almost impossible to find new.

You can still buy them readily online though. The Philips can be had at American Satellite for $99 shipped. This is your best bet. You would pay $99 plus tax for it at Circuit City assuming you can find a new one. There are other online retailers like OrbitSat.com, but they seem to be getting a bad reputation lately (I have bought from them in the past without incident).