I have two machines, and I use them both with great results.
For small jobs, the Donvier Ice cream Maker is perfect. It has a 1-quart capacity, and freezes ice cream with a manual hand crank in about 30 minutes. I like to bring it to the table and have guests do the cranking.
For larger jobs, the White Mountain 6-quart electric model does me right. It's messier (you have to use rock salt) and louder, but you can set it up and walk away, returning to perfectly frozen ice cream in under an hour.
For a list of stores and prices, read on.
The White Mountain 4-quart electric model is available at Cooking.com for $199.95
The White Mountain 4-quart traditional crank model is available directly through White Mountain for $139.95
The Donvier 1-quart crank model is available at Cooking.com for $49.95