So I've been doing the Insanity workout now going to the end of week two and I'm worried that I should be seeing more results. I work as hard as I can yet some people say they have lost a lot of weight in just a couple of weeks. It can also be sometimes disappointing when I work this hard and then I'm seeing anything...

First off, two weeks is a short time, in terms of seeing results, so don't lose heart!

Second, are you watching what you're eating? Exercise is great, for general fitness and to burn off some extra calories, but you can very easily eat back all of the calories you burn with exercise if you don't watch what you're eating. You might burn 400-500 calories in a workout, but if you eat those calories back, you won't lose weight, even if you are getting fitter and stronger. Weight loss is basically about calories in vs. calories burned...if you eat fewer calories than you burn, you'll lose weight.

Exactly.

Insanity is not a weight loss program it is an exercise program which is marketed as a weight loss program. Insanity is fantastic for building your cardio endurance if that is what you're after.

Personally I think your time would be better spent lifting heavy weights if you're after fat loss and body composition but what is most important is an exercise routine you enjoy so you stick with it for a long time.