Most coaches are willing to help in every way possible, but you need to realize their limitations. First, you need to understand his/her schedule. Most coaches teach all day. In-season, they are coaching for another two or three hours, then go home. This leaves them with about four hours in the evening to themselves or families before the "sleep monster" grabs them and carts them off to bed. How much time do they really have to devote to getting your information out? Secondly, not too many high schools have money set aside for coaches to do mailings and pay for long distance calls to colleges.
If you're serious about playing sports in college, you should definitely ask your high school coach for help. But you need to take control of the recruiting process yourself, too, by making sure college coaches know about you.
For more information about how to get noticed by colleges visit Varsity Pages at http://www.varsitypages.com/kyspecial.html