It depends on the Pokemon you're trying to evolve. While some Pokemon can evolve without any problems due to being in the regional Pokedex, other Pokemon (Golbat, for instance) won't evolve without the National Pokedex. Note that this is only the case in FireRed and LeafGreen - in later games, Pokemon not in the regional Pokedex will evolve, but won't be recorded until you get the National Pokedex.
There are only two Pokemon(without the National Pokedex).They are Pickachu (into Raichu) and Eevee (into Jolteon).
Once you have completed the pokedex I think you should try and evolve them all and then get them all to level 100 although its impossible to complete the pokedex without an action replay
no not possible or get national pokedex from rowan then migrate, then go to pal park.
the kanto pokedex YES national not sure but i think you have to trade from ruby or sapphire or something
By trading it in from elsewhere, eevee is not available in the main Diamond/Pearl game before the national pokedex. When you have the national dex, however, you just go to see Bebe in Hearthome, in the house right next to the Pokemon center.
the number says ???
you have to trade them from a game that has the national dex.
no
You must have the National PokeDex to capture Heatran.
you cant
you need a cheat for it.
you can't
eterna forest 10%
You can catch them on Iron Island once you have the National Pokedex. You get this by seeing all the Pokemon on the Sinnoh Pokedex.
you have to get 150 different types of Pokemon
it is not possible to get them without evolving or trading.
You have to have the national pokedex, because you cant find a lot more Pokemon without it. :)