First off, you should definitely check out Jordan Malik's material. Lots of free resources to get you started on your Amazon path. There's a popular podcast called "The Amazing Seller" with very good information.

If you want to start selling on Amazon, treat it like a business. It takes a lot of time up front, particularly in finding a product and learning the ropes. There is no magic formula. If you want to be successful, you should expect to continue to work at it. It's not a matter of "post your product on Amazon and let them fulfill your orders while you book your world cruise." You will manage suppliers, do marketing, work with customers, take care of accounting, develop new products, etc.--all the things that a traditional business needs to do in order to be successful.

Is it a good busy model? Yes. A lot of people are finding success on it. It's fairly straightforward and requires less time and money than many other ways to sell products, like starting a brick and mortar store. It takes work though.