You need to make a business plan and start executing it. First your son needs to make an honest assessment of what level of college ball he CAN play, not what level he wishes to play. Then this the conferences at the level he believes he can play. From each conference choose the schools that fit from a baseball, academic, geographic, social and financial standpoint. It's ok to have a list of fifty schools. Some won't be interested in him. Some he will decide he's not interested.
Figure out your budget. Can you afford to pay for an expensive travel team? Or would pinpointing individual showcases and camps be a better financial fit? If he's going to play travel you need to find out the travel teams to get on soon. Most tryouts are anywhere from now to January.
If he's a potential D1 or D2 player he needs to register with the NCAA Clearinghouse online.
Do not rely on just high school coaches. If they can help, great. Your son needs to control his own destiny. He can do that with a business plan and keeping notes on everything that occurs. Don't be afraid to ask questions on this site.
Where do you live? People here can probably suggest travel teams and showcases to check out. How far away from home is your son interested in attending college? What level player (D1, D2, D3) is he? A quality high school and/or summer coach may be able to provide an honest talent assessment.
Relax. You're not behind yet. Summer/fall after junior year is major recruiting time. But you need to track down and tryout for travel teams between now and January. Read the section TPM suggested to get the big picture.