i think you have to ether level him up at mount coronet or make him level up while wearing a certain item at mount coronet
Electabuzz, Voltorb and Magnamite can be found in the Powerplant alone with Zapdos. They're powerful (especially Electabuzz) and Voltorb can be evolved into Electrode; an explosive Pokemon. Magnamite can evolve into Magnatone, and if transfered to other games, a Magnazone.
A Magikarp should evolve at about lvl 40 on Pokemon diamond
Cranidos is a Rock type Pokemon that can be revived from a Skull Fossil in Pokemon Diamond. It will evolve into Rampardos at level 30.30
it doesn't you evolve it in a trade
Ponyta evolves at Level 40 in Pokemon diamond.