Without trading, Pokemon Ranger, and/or action replay, it is not possible. (I don't know if Manaphy is 150 or 151 in Sinnoh Pokedex.) You need Pearl or trade to get Glameow, Purugly, Misdreavus, Mismagius, Shieldon, Bastiodon, and Palkia. If you have seen Pokemon besides the ones that are only obtainable in Pearl, legendary, or the Pokemon starters and evolutions, look at the area in your Pokedex. They should be there unless they are some bigger evolutions, or honey tree Pokemon and evolutions (honey tree Pokemon are Cherubi, Aipom, Heracross, Munchlax, all Burmyforms, and Combee). You need to beat Pokemon Ranger to get Manaphy (you can search the answer to find Manaphyegg). You can search the answer to get legendary. But only Riolu is a Pokemon whose area you can't find. Go to Iron Island, help the lost person, and he gives you an egg. It later hatches to Riolu.
go to hearthrome city there in one house bebe will be there she will give you eevee
you need to see 210, you need to see 150 for Pokemon diamond and pearl
To know that, go to http://serebii.net/pokedex-dp/ and search for any pokémon and it will say you where to catch it (that site don´t say how to catch the legendary pokémons, however) in pokémon diamond and pearl.
you have to see all Pokemon in the game (sinoh only) and the go to see rowan the profecer and oak will appear
Names of the first 150 original Pokemons:BulbasaurIvysaurVenusaurCharmanderCharmeleonCharizardSquirtleWartortleBlastoiseCaterpieMetapodButterfleeWeedleKakunaBeedrillPidgeyPidgeottoPidgeottRattataRaticateSpearowFearowEkansArbockPikachuRaichuSandshrewSandslashNidoran (Female)NidorinaNidoqueenNidoran (Male)NidorinoNidokingClefairyClefableFoxfireNinetailsJigglypuffWigglytuffZubattGolbattOddishGloomVileplumeParasParasectVenonatVenomothDigdaDugtrioMeowthPersianPsyduckGolduckMankeyPrimeapeFlamieBlazePoliwagPoliwhirlPoliwrathHocusPocusAlakazamKara-teeKung-fooJu-dohBellsproutWeepinbellVictreebellJillMan-o-warGeodudeGravelerGolemPonytaGallopSlowmoSlowbroCoilRecoilFarfetch'dDodoDodrioSealMantyGrimerMuckShellderCloysterSpiritSpectreGengarOnyxDrowzeeHypnoKrabbyKinglerVoltorbElectrodeExegguteExeggutorOrphonGuardiaHitmonleeHitmonchanTonguetydNYLARhyhornRhydonLuckyMeduzaKangaskhanHorseaSeadraGoldyNeptuneStaryuStarmieMr. MimeStrykeJynxElectabuzzMagmarPinsirTaurasMagikarpSkulkrakerNessDittoEonVaporeonJolteonFlareonPorygonEssKargoAttLantisPteraSnorlaxArticunoZapdosMoltresDragoonDragynDragoniteMewtwoMyw
in the grate marsh
Pokemon number 150 is Palkia, you can get it on the pokedex by trading, battle a friend or seeing the old lady in the library who shows you a picture of Palkia which is then added to your pokedex.
Pokemon Number 149 (Dialga) Cannot be found in Pokemon Pearl, he is only available in Pokemon Diamond, where as Number 150 (Paulkia) cannot be found in Pokemon Diamond. If you need to fill the spot to complete the PokeDex, you can see #149 from a lady in Celestic Town.
you have to see 150 Pokemon then talk to professor oak..
150
there are exactly 493 pokemon, i know!
In the National Dex, Mewtwo is Pokemon number 150.
for diamond and pearl there are 150 Pokemon u need to see . in plat nium u neeed to see 210 Pokemon.
First you have to find all 150 Pokemon then talk to professer rown and then you p. oak comes and opens it. And you then get the national pokedex.
Pokemon 150 is Palkia, the Space Pokemon. You can find it at Spear Pillar.
See all 150 Sinnoh Pokemon
Palkia is the last Pokemon in pearl and in diamond you find him in a book that an old lady shows you and in pearl you find at spear pillar on mount coronet. (I really hope this helps you on your wild adventure)