A great drill to learn to keep your eye on the ball is to play dodge-ball. I know it sounds kinda corny with the new Ben Stiller movie coming out, but in this exercise you are forced to keep an eye on the ball at all times so it doesn't hit you. I found it particularly helpful to move to smaller and smaller (up to a tennis ball size) balls as your coordination progresses. Try to see the ball all the way til it gets to you and catch it.
I know some of you (including me) may think you are too old to play this, well, you are not, and you can always play with just one other partner throwing balls at you. You can make beer bets to see who dodges or catches the most balls. Or a ball machine is very effective as well if you have one and are all alone.
Racquetball is a good 2nd choice in my opinion.