Hi Larry,
We will definitely need some clarification on what kinds of turns you're thinking of, since there are so many possibilities, and the technique can vary so much from one turn to the next.
There are the basic turns in the smooth and standard dances that you take in closed position (e.g. Left Box / Reverse Turn in Waltz), various underarm turns of free spins in Swing, Lindy and Jive (e.g Underarm Turn to Left, American Spin), Spot Turns, Switch Turns and Walkaround Turns in the Latin dances, and even generic 3-step turns, twist turns, chaine turns, etc that can apply to any dance, just to name a few.
Give us some context and we'll try to help you with some information and exercises.
Regards,
Jonathan Atkinson
BallroomDancers.com