First off, some terminology. You will not be selling homebrew under any circumstances. Getting set up in your area to sell alcoholic beverages will automatically put you into a whole different classfication - and homebrew will not be in the title.
If you are in an area with a brewery, go check them out and make some inquiries. Next, call your city or county clerk, i.e. the place that collects money, and simply ask them what is required. Make sure you know what you're really asking - getting classified as a brewery is probably different than getting set up as a brew pub. However, either one will require contact with multiple agencies between federal, state and local. Alcohol laws are goofy almost everywhere and every bureaucrat wants a piece of the pie. Be patient and let us know what you find out.
Prosit,