while creatine IS one of the supplements that does work, you need to understand HOW it works.
in simple terms, your muscles work by using calcium in a chemical reaction that binds parts of the muscle fiber together to contract the muscle. Sorta like two gears turning together, except it actually bonds together at each 'tooth' in the gear.
what creatine does, is breaks that bond so the gears can turn another notch..another notch...another notch...until you've reached maximal contraction.
So really creatine 're-cocks' the muscle so it can keep contracting all the way. when you run outta creatine, you just won't be able to keep moving the weight.
Essentially creatine is for 'endurance' during a set of lifting. Its beneficial because if you can bust out a few more reps, that should put you a little deeper into hypertrophy. As long as your diet and recovery time supports it, the extra hypertrophy should equate to building larger, stronger muscles.
good creatine monohydrate with the creapure stamp on the back should run $15 for 500g, which is a solid 3 month supply. no need to load, no need to cycle unless you just feel like stopping it. 5g a day, post workout.
but, if you're not eating enough, or eating the right stuff, creatine won't give you big muscles.