I can usually catch shrimp near dock lights at night in pretty good numbers.
Use this video to help you with throwing the net. I learned this method from this video and can catch any bait now. Even dozens of schooled mullet in 40 feet of water. The guy on it is a yankee but oh well..
[nomedia="http://www.youtube.com/watch?v=lOUkj2h2LjI"]YouTube - How to throw a cast net[/nomedia]