My brother was diagnosed with non-insulin dependent diabetes mellitus. what does this mean?

No insulin needed: That means his diabetes can be treated with oral medications and that he is not a type 1 diabetic. The Insulin in his body is not working well so the treatment is to do anything to make the Insulin works better: weight loss, increase activities/exercise, medications...

Type 2 diabetes: The first source of information would be the american diabetes association, which has available a huge amount of literature on the subject. One can look up diabetes on google - but be careful that you realize that the material might not necessarily be checked for acuracy. I have recently released an informational dvd called "diabetes swweet 'n simple" which discusses the basics of the disease.