You ask several questions, which I'll try to shed light to. First of all you should become very familiar with the "recruiting Tips" section of this website. It is invaluable to a student athlete looking to continue beyond high school.
The letter players receive vary from mail-merged mass mailings to hundreds of players from top 30-40 type teams to personal handwritten notes and cards from coaches at all levels. Some schools send out very little mail at all. Some are sending sophmores Christmas cards signed by all the coaches.
What do coaches have to say on July 1. If they don't already know they want to find out if you are interested in them. They may ask you straight up or wait for you to express interest.
If you are fortunate enough to get visit offers early and you have interest, take the visit as soon as possible to leave time for additional visits. You can start visiting when classes start and they like kids to visit during football weekends. Visit the schools highest on your list the earliest. Often times, the first player to commit on the coaches list is who gets the spot. It may not be the most scientific recruiting process, but thats how it works.
You are allowed 5 visits to different schools. Getting 5 visits in if they are offered is difficult at best. Most kids are lucky to get 2 or 3 visit offers, let alone 3 at schools they could or would attend. Most times you will be offered on the visit. Getting Visit #1 school to wait 5-10 weeks for you to visit 4 more schools is sometimes not practical for you or them.
Its all about getting you ducks lined up then.......keeping them lined up. Good luck!