Here's a good link to explain what Creatine does and how it works
http://www.bodybuilding.com/fun/layne13.htm
When using it for bodybuilding purposes, you need to make sure your workouts are utilising higher reps, don't work out in the 6-8 rep range or you'll get no benefit from it. Creatine helps strength endurance (10 reps and up), you can get an extra rep or two out if you're on it and respond well to it.
If you eat a lot of red meat, you might not notice much notable benefit form supplementing creatine.