start of with this site --
http://talk.collegeconfidential.com/
It depends what college you want to get into
Make sure you're in some honors/ap classes and study hard in them.
For a top 25 school like UCLA, duke, Berkeley you really need a high gpa like 3.8, with a good sat 2100+.
For ivies- there out of your reach
For state schools, usually top 25% is good, 3.5 GPA at least and take as many advanced classes as you can handle while maintaining mostly A's
For
top state schools like UT austin, NYU, and any University of California you will need top 10% with involvement in what you like, and a good sat score.
Top 10%, with good extracurriculars, and a SAT of 2000+ will get you into a great college, but is not necessary at all.
Take the PSATS and apply to colleges that send you stuff if you're worried about money ( a lot of them offer full rides ), if you want to go to a really good college you can always wait till grad school if you want....
Also schools have this thing called estimated family contribution, so if you're family only makes around 30k-60k you're not going to have to pay much for college since colleges will only expect your family to pay around 1k-3k so basically after 1-3 scholarships you got yourself a full ride.
As the above poster said see about a masters or a graduates degree (mba, M.D, D.O) it will greatly help you
and first of all MAKE SURE YOU VISIT THAT SITE! Believe me it has a wealth of information!