Veilstone City
In lilycove city.
In Lilycove. The big skyscraper is the pokemon mart. Just go up the floors, and they sell different items.
HM04
In Pokemon pearl, Pokemon 149 is Dialga. After you've beaten the Elite four, fly to Celestic town, and got to the big house at the north end of the town. Look in the book on the table, and you should see Dialga in there!
Veilstone City
You buy it in veilstone city the big shopping mart's floor 4 OR 3 its one of them alright
In lilycove city.
If you mean diamond & Pearl, then in Diamond, Dialga and in Pearl, Palkia
If you mean the big department store, it's in Veilstone city.
In Lilycove. The big skyscraper is the pokemon mart. Just go up the floors, and they sell different items.
HM04
in the cave with big boulder
Rpute 7 is between Saffron City and Celadon City (the city with the big mart).
There are Pokemon centers in every town that you visit and they have a red roof with a big red Pokemon ball symbol on the front. The Pokemon mart has a blue roof and a blue Pokemon ball symbol out the front. Both the center and the mart has a sign outside so you can check which is which if you are confused.
It is the Lustrous Orb. Give it to Palkia to power it up.
get 2 ds' and in pearl when you turn the ds on go to the bottom right that says ds wireless communications and then in black go to route 15 and there is a big building where you can transfer your Pokemon to pearl