What would A person need to legally travel from Mexico to the United states? e.g Visas, permits etc?

Visa

As of the 15 of January 2007 passport.

Lord, I suggest you PRAY really really hard for that answer

Visa, or passport

Hypothetically speaking, you mean? A visa.

Your entrance requirements depend on your citizenship, not where you come from.

If you are Mexican, you need to apply for a Visa. If it's a short-term stay a travel visa can be issued at an American embassy or consulate (relatively easy). If you want to stay for a longer period of time, study or work, the requirements are tougher. Check out the link or ask the embassy.

Any of the below:

1) tourist visa
2) resident alien card (greencard)
3) student visa
4) temporary/seasonal workers visa

to qualify for them you must show proof of intent and the money and properties you possess or have a monetary sponser.

a visa or passport. Also depends on if a family member is sponsoring u on the visa or a school