Smoking kills.period.
Vaporization eliminates the toxic particles by heating the herb to a boiling point rather than to an ignition point.No tars are produced,neither are most of the carcinogens that are produced by burning.
There is no shortage of info available into these devices,but most recommend to avoid the direct heating methods which generally do produce some level of ignition,and stick to the convention/hot air heating methods.Temperature control is very important too as the difference in temp to acheive a boiling point over a flash ignition is not all that great.
Prices will range,on a quality unit,between about 200$ to 800$.Many justify the expense not only on the health aspects,but also on the efficiency of this method. A fraction of the herbs are needed as opposed to conventional smoking,since very little is lost to the air.
Also the smell is much less offensive.