Francis,
You asked about D2 and D3 colleges - My son will be a sophomore this year at a D3 school that costs about $20,000 per year for tuition, room and board, plus another $1,000 or more for books and fees. Many D3 colleges in our area cost much more than this, in the $30-$40,000 range, but this was his first choice of schools. D3 colleges are not allowed to give athletic scholarships, only academic and need-based. My son only received about $5,600 in financial aid/scholarships the first year, so the rest of it needed to be paid by us - it's really quite difficult.
You are definitely headed in the right direction by thinking about academic scholarships if you choose a D3 college! I believe it's fairly common in our area for a very good student to get 25% to 50% of their college costs paid by academic scholarships, and a few of the very top students get close to 100% paid. Good luck to you!