When the body forms stones in the kidneys and/or gall bladder it's usually a sign of toxidity in the body.
In the case of the kidneys it can be related to an underfunctioning kidney that fails to empty thoroughly through normal urination. The retained waste that's not eliminated sits and putrifies in the kidney and the stones are formed. A toxic system exacerbates the problem as the waste urine is usually higher in toxins than is normal. Again, this promotes the formation of stones.
The organs responsible for removing waste from the body are the colon, the kidneys, and the liver. Detoxifying these organs is key to eliminating toxidity in the body. Detoxifying is done by use of a flush or flushes (multiple).
Here's a site that explains this topic pretty well:
http://www.the-natural-path.com/toxic-cleansing.html
I can attest to the effectiveness of these flushes through my wife's experience. When my wife and I were married she had a very toxic liver/gall bladder/colon. Because of this she had a great deal of difficulty digesting and eliminating foods. The MD's told her that she had so many gall stones that gall bladder removal was the only solution to her problem. The trouble with this diagnosis was that the MD's "solution" didn't address the underlying problem that
caused the gallstones in the first place - the toxidity in my wife's system. And gall bladder removal meant a life of drug dependancy as well.
So, I dragged my wife (almost literally) to a Holistic doctor who first worked on her toxic colon (which was quite bad), and then he had her do a liver/gall bladder flush. To cut to the chase, at the end of the flush my wife passed hundreds (yes, hundreds) of gall stones from her body. It was incredible. Not only was her gall bladder free from gall stones, but her whole digestive system finally began to work properly. Her overall health and well being increased dramatically, and her ability to lose weight naturally went way up. My wife today is so conscious of how her system works/is working that she is in the best shape of anyone I know at her age. Because diet is so important in why our systems become toxic in the first place, she has altered what she eats to promote the health of her system. And, she doesn't suffer because of it. She still eats things she enjoys, just not often or in large quantities for the "bad" stuff. Without a concerted effort to specifically lose weight, my wife has dropped 2-1/2 dress sizes since when we first met.
In my wife's case her kidneys were functioning properly - which is surprising with what we now know. But, as part of the "triad" of organs responsible for the removal of waste, the kidney can be treated similarly.
There's plenty of good info on the web for you to check out, FrankenFretter. And I'd highly recommend finding a good Holistic doctor near you to help you along. In our household we see our Holistic doctor first when a medical problem arises...short of anything requiring heroic medicine (broken bones, lascerations, etc.). My wife is a healthy living example of the benefits of the holistic approach.