cub1jon,
Division 3 colleges cannot offer athletic scholarships - that is, they cannot give you baseball money. Any reduction you receive on the cost of a D3 school would be for:
Academic scholarships based on things like grades and ACT or SAT scores;
Need-based financial aid which depends on your parents completing a FAFSA form; or
Other miscellaneous scholarships (like a local group awarding $500 based on an essay contest you enter through your high school).
It can be surprising how the financial aid can vary at different D3 schools. One school might cost a total of $20,000 per year but only offer the student $2,000 in total financial aid, while a more expensive D3 at $36,000 might offer $18,000 in total aid, making the out-of-pocket cost (to you and your parents) the same ($18,000) for both schools. Some colleges will have an area on their website which tells you the average financial aid being received by their current students. And a few schools even publish a specific academic aid policy, something like 25% tuition reduction if you have a certain high school GPA and ACT/SAT score. But in most cases you will need to have some discussions with the Admissions and Finanical Aid departments at the colleges you are most interested in, and ask your parents to complete a FAFSA to get some idea of how much aid your family might receive.
You can find out a LOT more about the FAFSA and financial aid in general at:
http://www.fafsa.org And you or your parents can fill out a preliminary FAFSA-type questionairre to start to get an idea of the total amount most colleges would expect YOU to pay out of pocket (your Expected Family Contribution), at:
http://www.fafsa.org/calculators/finaidestimate.phtml Good luck!