I gained, from the wealth of knowledge in these threads, that Optimum Nutritions 100% Whey is a good bargain. My favorite thing about it is that I can get 29 grams of protein per scoop, and the scoop is the same size as the whey I used to use that only gave me 20 grams per. So now I save on servings per container.
For added fat and protein I add a 1/2 cup of cottage cheese that gives it a frozen yogurt flavor. OTher fats peanut butter, whipping cream, flax oil, etc.
For carbs you can add some oatmeal or for post workout some graham crackers. Other add berries of various types, apples, bananas, etc.
Flavorings in my drinks involve cinnamon, splenda, coffee, others here have mentioned Crystal Light.