Incorporation is a state-level activity, but it's generally the same in all of the states.
Use a parent's address with their permission.
Are you sure at this point that you need an address?
Maybe you're already past that discussion, and if so I apologize. But I have seen quite a few cases where folks rush out to file paperwork long before it's actually necessary.
I use it and it works pretty well - in many ways it's better than a PO box. Actual physical address, no paper to deal with, and you don't have to drive anywhere to get your mail. The interface is a little sluggish, though (ASP & MSFT Servers...) - but they say they're working on that.
It's great if you don't want to change your address every time you move.
That being said, neither a UPS Store box or a residential address is exactly going to impress folks if they bother to check out your business address before decided to ink a deal with you.
The only downside was that my business credit card offers got mixed in with my regular credit card offers.