Consultation on incorporating a business in the US

Hi, I'm a non-US resident and would like to incorporate a business in the US to protect my assets and be able to process credit card payments online. I'm currently staying in the US under a B1 visa, and will return to Europe in a few months. I'm looking for someone who could enlighten me on the following matters: - as a non-resident, what taxes will I have to pay, and how will I do that? - should it be an entity of its own or a subsidiary of a European company? - as a non-immigrant on a B1 visa, can I own shares in a US company as an active member? - where should I incorporate it? Corporation or LLC? What are the ongoing requirements? I would favor someone who could act as my expert lawyer for ongoing matters, including actually incorporating the company and taking care of compliance/be my registered agent.