This is an interesting question that is posed all the time and in many different forms. I can speak from personal experience only and by no means consider myself an expert on the subject.
In my view, there are at least two major requirements to be fullfilled before you can play at any given college. 1) There has to be a need at your position, and 2) You have to be good enough in the coach's mind to play for that school.
Regarding 1, if they signed three freshman All American's at your position the year before, it would seem doubtful you would even want to attend that school let alone have a decent chance of making that team. The quickest way to find these type of things out is check the current rosters out on the respective team's web site (i.e., do they appear to have a lot of graduating seniors or juniors at your position...they probably recruit pitchers every year however). Also, I know this may seem awkward, but try calling the respective schools of interest and ask to speak to the coach or assistant. In my novice days, I picked up the phone and called Stanford. You know what? They took my call!! I spoke with Coach Stott and he was way more than gracious and kind with me. He offered me valuable advice which I will now elaborate in # 2 below.
Regarding 2 above, Coach Stott told me they only recruit players they have PERSONALLY seen play. It was too late at the time, but he said my son would have to attend their camp which was one of the hardest to get into in the nation BTW. You know where most of the D1 players come from that play for Ohio colleges? Ohio! Gee why didn't I think of that. Not trying to be cute, but life is not as complex as it seems sometimes.
Once you know this type of information, you can then devise a plan. You could attend a showcase on the west coast/south or attend a specific college camp to get before the coach's eye. There will be no doubts whether you are good enough to play for them or not. The cool thing about these camps is, they are often represented by several colleges. All it takes is one to fall in love with you. Even cooler, if you attend during your sophmore or junior years, you can get on their radar screen, find out where you need to improve, and blow them away at your next opportunity before them. It is really all up to you. Hope this helps.
PS - There are other critical, non-athletic requirements as well. For instance, the first question Coach Stott asked me about my son was what was his GPA and what were his SAT scores. If you don't have excellent academics, I wouldn't spend too much time on ELITE academic institutions like Stanford. Your guidance counselor can help you determine these matters. If it is a close call, try asking the coach via a phone call as noted above.