Pokémon Crystal Tips

Note about finding shiny pokemon
Going to a certain location doesn't increase your chances of finding a shiny pokemon. It's all a matter of luck, even if other people say they have seen shiny pokemon in certain places that doesn't mean that you'll find them. The only shiny pokemon you are sure to find is the red Gyarados at the lake of rage or the shiny Caterpie in Helix Forest. Other than that I'd say you will catch at least one shiny pokemon and see others.
Also, in some cases the pokemon don't appear to be shiny, but if you are the slightest bit suspicious of the color then catch it to be sure.