Where is a good place to find cheat codes?

I play some games on my IPhone, I have the GBA for IOS and I'm playing Pokemon Emerald right now. Where is a good place I can find cheats for this game? I found a couple, but the cheats unfortunately won't work. I'm mainly looking for Wild Pokemon codes, Rare Candy Codes, and the Master Ball Code. If someone can give me a link or just put the codes as an answer. I will be really grateful!

Cheatcodecentral.com