I'm also a qualified fitness instructor and personal trainer. The advice I was given by my lecturers during my course was that protein shakes etc aren't for your run of the mill daily gym user. All the protein you need comes in the forms dan just mentioned, most of which would be in most peoples daily diet. Protein shakes only work for people who train 2-3 times a day and can't get enough protein into them through normal diets so are required to "supplement". These are your professional weight lifters, fighters and athletes. The majority of this stuff you urinate out so it's an expensive trip to the toilet in my opinion.
If you're just a regular gym user, I would advise you to eat 5-6 smaller meals spread out across the day and never miss breakfast. This way your metabolism is working from the minute you get up until you go to sleep which means you're burning calories even when you're not exercising.
As for diet p*lls, I'm pretty sure they're just laxatives so again, another expensive trip to the toilet.
As for training, depends on what your goals are. If you're looking to lose fat but gain muscle I would train 2 muscle groups a day, coupling a larger muscle group like your chest with a smaller group like your biceps or triceps. do 3-4 exercises per muscle group, at least 40 minutes of cardio a day, and train 5-6 days per week if possible. Always give your body as least one days rest a week.
Hope this helps.