The cheapest and most effective way to cleanse the body that I've ever found *and I've done just about everything I've ever heard of* is juice fasting.
But a high raw diet, that is grain free, dairy free, free of most if not all GMO/inorganic stuff, that's the way to go. If you remove all grains and base your diet around leafy greens and living foods and salads, you will get HUGE results pretty much right away.
I've been grain free (including rice) since the beginning of 2011 and it's totally awesome! I haven't been sick since.
You should read the cleansing and naturopathy thread. I'll go find the link for you.