How would I get help starting a business from scratch?

Hi!

Basically, my brother and I have a business idea that has great potential…but we need a modern/current consulting company to tell us what to do next.

The business model calls for partnerships with several MAJOR companies already in existence. I know we’ll need a business plan, lawyers, a solid pitch, etc…but I’m wondering if anyone knows of a good company in the NY/NJ area that can help us take the proper steps in starting the business – from absolute scratch!

… basically someone to hold our hands and help us take care of all of the start-up legalities and processes.

Anyone know anything about this? Would companies like this charge their fees upfront, or would they allow a grace period until the company is up and running and profiting?

Anyone have any websites/links/contacts?

Thanks!