Rather than spending weeks digging through conflicting information online, we suggest you start with compilation of resources.
Test Registration
SAT Registration
ACT Registration
SAT Subject Test Registration
AP and PSAT : Contact the guidance counselor at your local high school
Free Test Preparation
SAT Question of the Day
ACT Question of the Day
Khan Academy SAT
ACT Free Test Prep
Scholarships and Financial Aid
Free Application For Federal Student Financial Aid, FAFSA
Financial Aid Information
Scholarships: Fast Web
College Search and Admissions
College Board Big Future
Common Application
Coalition Application