Generally you are not given the entire financial aid packet to fill out until you have been accepted. However, when you file your FAFSA, you indicate which schools to send it to. Often at the interview, the financial aid people will encourage you to do this early, even before acceptance since all you are doing is checking a box for their school.
The scholarship + acceptance you are probably hearing about are merit based, not need based. These scholarships are often given to entice good applicants to come to a particular school.
Many schools do not have merit based scholarships, or only have a few.
