hello
registering a company is really easy.
go to your local Court. (the place you go for your traffic tickets)
you'll give them name of your company + $13 registration fee, and that's it. your company is officially registered. then you have to get an tax ID. it should be on the same building, if not, they'll give you the exact address and map for it. after you done, they'll mail you all the legal papers (tax ID, etc..). in about a week or two.

benefits?
first of all, you can open a business account at your local bank. Washington Mutual offers free business checking. you can build up credit for your company. they'll issue you a credit card under the name of company, if you get approved. you can use your business checks for purchases related to your company. when you do business with people, they prefer to right the check under the name of company rather than an individual.
anyway, it's a good thing to do.