you must trad a porygon holding an up-grade
An Up-Grade is an item that evolves the Pokemon Porygon when Porygon is traded while holding it. Porygon evolves into Porygon 2.
evolve porygon from veilstone city
Link trade Porygone while it holds the Up-Grade
you give porygon the upgrade then trade it to get a porygon 2 then you give your porygon 2 another upgrade and trade yet again to get a porygon-z
find porgon 1 and catch it then in the closest bit of grass you will see porgon 2
trade while holding up grade and it will evolve into porygon 2
In Pokemon Platinum, Porygon-2 can evolve into Porygon-Z using the Up-Grade. I do not believe it serves any other purposes.
In Pokemon Platinum (I don't know about Diamond and Pearl), Porygon is located in a house directly behind the Pokemon Center. If you want to evolve into Porygon 2, trade it holding a Up-Grade, and if you want to evolve Porygon 2 into Porygon Z, trade it holding a Dubious Disk. I do not know where htese items are found. If you want to get Porygon the harder way, use Pokecheck.
one of the scientist in the galactic warehouse.
Have a Porygon hold it and trade it.When the other person gets it, it will evolve into a Porygon-2.
I believe the only method to obtaining Porygon 2 is by evolution. You do this by giving a Porygon an 'Up-Grade' item and trading it.
You go to celestic town then go to the left to mt. cornet then go north the first trainer you find has porygon 2