Either cheat...
OR you can use the pokeradar and build up a really long chain. Eventually, this will find you a shiny pokemon.
OR you can wander around and take the tiny chance that you will randomly encounter a shiny pokemon.
OR you can slightly increase these odds by breeding different nationality pokemon, the baby one will be slightly more likely to be shiny.
buy the Pokemon platinum book
The 151st Pokemon is Mew and is unobtainable in Pokemon Platinum.
no you can't find a torchic egg in Pokemon platinum
defeat the Pokemon league and then talk to prof Rowan and he should give you a poke radar. Then go to the patch of grass outside canalave city and use it. If there is a sparkly patch of grass go to it and you should find ditto.
try your best to find spirtomb in Pokemon platinum
You cannot find zekrom in pokemon platinum
There is not a route 233 on Pokemon platinum.
there is no such Pokemon
you find them in the cave
breed an electabuzz if you want an elekid in Pokemon platinum
You can't "find" him. You have to trade the egg from Pokemon ranger over to platinum, where you can hatch it.
You cannot find Lugia in Pokémon Platinum.