Here are several links that I've discovered over the years that you might find helpful:
http://www.youtube.com/watch?v=0_vR8U_KrhY
Don't use a weight in the on deck circle. You're hurting your bat speed and coordination.
This site provides several resources including a search of colleges within user-defined parameters.
The Baseball Factory provides a number of services from individual instruction to college recruitment help to various showcase type events. One of the highlights at the Baseball Factory is Matt Schilling - simply the best hitting instructor I've ever seen or heard!
This site takes you to John Dopson, a former major league pitcher (5-yr career), who provides individual pitching and hitting instruction. I've seen John work with kids and he's excellent.
If you know of other links that might be useful to our friends, please let me know and I'll add them here.