What is needed to digitally sell and distribute software (videogames) to the US?

I'm currently developing a game with a few friends and have plans to sell it and distribute it worldwide via digital means. I'd like to know what I should take into consideration if I want to sell the game to U.S. consumers (For instance, what the legal requirements for selling digital goods to the U.S. from a foreign country are). What about worldwide?

We will have physical presence only in Peru.

P.S.: Although the U.S. seems to have lower taxation than Peru, making the consideration of establishing the business there attractive. So as a second question, do you know what it takes to set up a business in the U.S. if one doesn't have American citizenship? Even links to resources would be fine.

P.P.S.: I found this question, and as much as I trust Joel's knowledge, I'd like a second opinion :P

The United States is actually considered a Tax Heaven, (not as much as panama), but still as compared to many other countries.

Nothing is required for you to attract US customers. The united states does not restrict foreign corporations for doing business in the states expect for rare cases such as pharma and other highly regulated industries.

If you are targeting a US audience its best that you host your site in the United States. Again there are no restrictions on this. You could even incorporate in the US (choose a state), form a business using an agent or attorney, and get a US bank account without being a citizen.