In choosing a roaster, the main issues are 1) how much coffee you generally drink and 2) how much you want to spend. You don't want to have more than 3 days supply of roasted coffee around since that defeats the purpose of home roasting; to always drink freshly roasted coffee.
There are many ways to roast coffee, from home appliances made specifically for this purpose, to simple pan roasting. Before you get started, we highly recommend checking out our General Roasting Instructions and Visual Guide to the Roast Process.
There are small, dedicated home roasting appliances, and we carry a number of these machines. Our article, Choosing a Home Coffee Roaster is a good introduction to the various models; the Roaster Comparison Chart compares the all the roasters we carry.