Ask HN: Business name availability and issues.

Is there a website or something where you type in your desired business name, and it displays all the names of all the companies with the name within all 50 states?

Also, is it ok if my business name is Example, LLC while someone elses is Go Example, LLC? With just the Go at the beginning?

And, I have a company name which is used by someone else in a different state, but theirs is Example while mine is Example, LLC. They sell designs online, I make apps for the app store. Any problems there?