I posted its info on the other thread when you inquired about it, heres what i said in case you didnt see it:
L-GLutamine is good for stopping muscle breakdown and encouraging muscle metabolism. After excercising, the stress and trauma can cause glutamine levels in the body to be reduced to as much as 50%. It helps against deterioration. Also up to 400% increase in groth hormones can be reached with just 2 grams of L-Glutamine.
If you overdose, you can get stomach aches. However a good amount for bodybuilders is around 10 grams.
Dont take my word for it, Im not a nutritionist, so you should research it as well.
You can get a good amount of it in soy protein. Soy protein also has a lot of arginine (what is used in Nitric Oxide). Whey on the other hand has a lot of the BCAA (Branched Chain Amino Acids).
2 to 3 grams post workout is a good amount.
Like i said on the other thread, I dont take any supplements except a multivitamin and flaxseed oil. It would help to go on it however its not required. Its good but you can live without it. It does help in battling muscle atrophy and helps to not break down when using glucose.