Help on my mission to Catch them all

hey guys.. i need some help.. for the past few weeks i had been trying to search for ways to get mew without doing cheat.. but it seems that it is impossible.. nevertheless, i was thinking of using action replay codes or game sharks codes to help me get the new in my pokemon diamond version.. i am using an R4 to play my game but yet i cant seems to find a good site that can really teach me how to use these codes.. can anyone kind enough to help link me to some good tutorial sites on how to load cheat file into r4 for my pokemon game? thanks a lot.. =]

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