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)
Here is a list of all 150 Pokemon: http://www.serebii.net/diamondpearl/shinoudex.shtml The last Pokemon listed (#151) is not required to get the national pokedex.
monferno
yes
unknown
in chroma road use slam 1 on a tree, the Pokemon is ninjask
In the National Dex, Mewtwo is Pokemon number 150.
I don't know about latest, but last in national Dex is #493 Arceus, Sinnoh it's #150 Palkia and #151 Manaphy.
nr 45 on the pokémon pearl pokédex is burmy
Go to Eterna City's Pokemon Center. Talk to the girl.
Pokemon nr. 267 is Regigas. Its in Hippowdon temple. Only as boss after capturing all 266 prior pokemon. Good luck! ^^
there is 150 Pokemon not 44
Of the original series nr 220. Shippuden is still going