When using mid to deep water crankbaits what type of weights should I use?  Also, how far up the line should they be?

Normally you don 't weight a crankbait, the bait dives when you reel it in.

Back in my "spoonplugger" days, we used pinch on barrel weights to add depth when trolling cranks for smallies.  4 to 6' up the line should be fine.  Any longer, and you'll have difficulty landing the fish.

The only time I use a crankbait with weight is when I'm trolling it in deep water, when I will use a carolina rig or a bottom bouncer. Most of the time, you just tie on a crank with a rapala knot and start fishing.

I have better luck with cranks when I can tick the tops of weeds or bump rocks and wood.