Recently many massage therapists have started using stones in their treatments, and not only in hot stone therapies. There are a number of carved crystal shapes specifically designed for use in massage, including flat palm stones, lenses, stylus shapes, spheres, massage wands and massage tools. Tumble stones are also very effective, and even rough crystals and crystal points can be used as long as you are careful of sharp edges.
It is best to learn this through a teacher, but there are also books available on the subject (eg. "Heal yourself with Crystals" by Hazel Raven). If you have some experience with massage, you can try working intuitively. Always use a very gentle pressure, as the deep work is done by the vibration of the crystals. Because of this, many massage therapists use this method if they are experiencing RSI or arthritis in their hands and fingers.