doc,
If you are using protein supplements and creatine, let me make one thing EXTREMELY clear. You must have a physical exam with urine and blood test after 3 or 4 months, to make sure you are not causing damage to your kidneys. EVERY serious competitive weight lifter or bodybuilder knows this, but many amateurs do not. About 1 week BEFORE having the physical, discontinue any creatine supplements, as these will throw off the results and cause an unusually high creatinin reading.
My sister is both a registered dietician and physical therapist and has studied sports nutrition extensively. As you begin weight training, your body becomes more efficient in utilizing the protein in your diet to build muscle. However you may want to add a protein shake with 20-30grams of protein following your workout if you are building up. A rule of thumb for weight training (provided you are in good health) is to consume 1.5g-2g of protein per 1kg of bodyweight. So if you weigh 220lbs (100kg) you would consume 150-200g/day of protein -- this figure includes all food you consume during the day including the supplement. Personally, I would suggest the low end of that range.
As for the wide range of supplements out there claiming to provide anabolic benefits (i.e. increase muscle building), aside from steroids (which will damage your kidneys), the only supplement shown to have significant verifiable benefit is creatine -- you can read up on the subject, if you take a look at research by Dr. William Evans (http://www.sportsnutritionworkshop.com/evans.htm).
As for myself, i weight train and after using creatine monohydrate (and not really enjoying trying to dissolve it in water and that not so pleasant taste) i switched to cee (MRI CE2) and have been happy with the results. I also take a whole food vitamin (not a megadose), fish oil, and a supplement for joints. I eat a ton of veggies, balanced with lean protein and go light on carbs. Before workouts I eat a half or full powerbar and drink lo-cal FRS which provides 1/2 cup of coffee's worth of caffeine. Good luck, and DO be careful, there's a lot of junk out there masquarading as nutrition or loaded with caffeine which is expensive and should be avoided.