Amazing experience, and wonderful views over the surrounding countryside. Lots of travel agents in Chiang Mai offer this trip as a half day tour in the morning for about 500B p/person and itís well worth doing. we did with www.chiangmaitotravel.com tour operator
I suggest catching the cable car up, and walking back down. The cable car is very cheap, I think about 30B (your tour should include the cable car).
In one of the temples, you can get blessed by a monk. The monk will tie a piece of string around your wrist, but only for men as they canít touch women. For women heíll drop a piece of string into your hand, and you tie it on yourself.
This was a great experience