The most common is a 5-day loading period of creatine of 20g per day, followed by a maintenance dose of 5g per day and some people actually cycle it. Wrong, wrong, and wrong. 2 days of loading will give you the same muscle creatine levels as 5 days of loading, so 2 days is more efficient and therefore is the better option. Once muscle creatine stores are saturated, they can be maintained with a dose of 2g per day and any excess will simply be urinated out. Re-loading is only necessary if you discontinue use for more than 28 days. Cycling has no benefit whatsoever, it was previously thought that by taking creatine for extended periods would down-regulate creatine transporters. But, contrary to what studies on rats have shown, actual human studies have proven otherwise. Creatine has also been shown to be absorbed better when insulin is spiked through a high GI drink, so if your diet allows, this may be something you would want to apply, especially post-workout.
In general, if you are getting enough protein you are getting enough glutamine. But, in times of great stress, and/or severe calorie deprivation glutamine becomes very important. When the body is under a great deal of stress the body releases glutamine into the blood stream (as much as 1/3 of the glutamine in muscle can be released). This results in the depletion of glutamine in muscle and is a major contributor of muscle atrophy. Through supplementation of glutamine, this can be prevented. Although studies have not determined the exact dosage that is optimal, but taking 10 additional grams of the amino acid should be enough to compensate for the decreased muscle glutamine levels in times of great stress (you might wanna experiment a bit). Personally, when I supplement with glutamine I take 3g upon waking, 3g pre-workout, 3g post-workout, and 3g before bed. Glutamine is also one of the few things that can increase growth hormone secretion, up to 400% after just a two-gram dose of the amino! But, because the effect is transient, the actual effect probably won't do anything significant to your body composition, even injectable GH doesn't work very well, so I can't see a supplement doing much of anything in this aspect.
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Complex problems have simple, easy to understand, wrong answers.