Pick a name And start building :)

I have a name, but do I have to form a corporation or anything like that?

I wouldnt bother with that unless you have a way of dealing with the taxes. how are you planning on selling your stuff? Alot depends on local laws, and where your going to operate the business. the only advantage of a corporation is that if someone tried to sue they could only get the company assets instead of your personal money

I would worry about that when you make some money heh. Look at your states website under small businesses for forms and rules, regs.

Start out as a sole proprietor. Depending on what you are making you might want to change over to an LLC at some point.

oh and if you want to make a living at it you really need to read up on starting a small business so you do your taxes right and price your products properly.

you can set up a dba with your local city government and when you want to set up an LLC for tax purposes it will run you around $1000

Nah, just do it all under the table.
Taxes are no different than charity, they're totally optional :)