This is probably one of my most preferred methods, but has taken me some time as well as frustration watching my boater catch fish after fish after fish.....http://rahfish.com/how-tos/tackle-tips/going-deep-with-small-swimbaits-what-you-need-to-know/. Use as light of a weight as possible, something you will hear time and time again from the pros and it makes a huge difference. I have been able to successfully fish deep water 30 + with an 1/8 jig head, the hard part is recognizing the bottom as well as a bite;most of the time its a light tick or pull, very hard to detect when you are just starting.
Forget the heavy jigs, go light as possible, start with 1/2 oz and work your way down to 3/8 if you can; my favorite is the keitech model 2 footbal jig. I guarantee you will out fish most guys if you can really get dialed in getting use to lighter weights in deep water. I know tungsten is expensive but its definitely worth it come tournament time for detecting subtle bites as well as the bottom structure.
My tackle is is a light to med light, extra fast tip is essential, with 6-8 lb test for spinning gear on this technique. For deep water jigs I prefer braid, usually with a 20 lb flouro leader on a medium heavy rod with a fast tip.
This technique, around ledges, rip rap, anywhere you can drag a jig has honestly doubled my catch rate.