Tigerfan_09, you don't say so specifically but from your name I'm guessing you're a rising senior.
If that is so, then you are at the point where the coach can call you once a week to communicate. You of course can also communicate by e-mail and by initiating a telephone call. The main thing that has changed is that if your call doesn't find him in or available, now he can return your call, whereas prior to July 1 he could not.
If you are playing for a summer and/or fall travel team, you should make sure the coach is aware of your team and your schedule. This will give him an opportunity to see you pitch in game action. If you're lucky, then this is his primary reason for asking you to come to a camp, so that he can see you perform in person.
If he's just trying to sell his camp, then doing it one player at a time is not very efficient, so I think it's reasonable to assume this is not his motive.
You might try calling to say, "I am very interested, I am going to come to your camp, would it be possible for me to combine this with a tour of the campus (etc.)? Will there be a chance for me to talk to you in person?" And send a follow-up e-mail including a schedule of when/where you will be pitching in game action.
If you get a response, and if they do help you to set up taking the standard prospective student tour the same weekend as the camp, this shows more than passing interest.
On the other hand, if you get to the camp and the coach doesn't bother to show up much less talk to you, that would indicate he felt he had bigger fish to fry. And while that involves you finding that out at some expense, if that's going to be the case, better to find out sooner than later.
If money is really tight and a big issue, you might try asking about the specific program and coach's reputation on such things before you pay the camp fee. Because the outcome will vary quite a bit from school to school.
E.g., we went to camps at UVA and UNC where all the coaches, including the head, were present all weekend and very active in communicating with players. At Clemson, we saw a lot of the assistants and we saw the head coach a little bit. A lot of recruiting discussions took place with players identified at these camps, on the spot. At N.C. State, in contrast, the camp brochure promised the presence of the head coach but he never showed, and there was very little presence even from assistant coaches. The camp turned out to be run by local high school coaches. There was no recruiting activity and no follow-up with players whatsoever.
So if you were asking me about a place I was familiar with, my answer would vary based on which school you were asking about. There is no "one size fits all" answer.
