Seven island at sevault canyon.
You can't
safari zone or kanto
You can't get a larvitar in the safari zone.
You need to evolve Lavitar to get a Pupitar at level 30 in Pokemon Diamond. Lavitar can be found on route 207 in the game.
No you don`t have to use the poke-radar to catch lavitar.
No only when you get the national pokedex
yes just beat the game and go to dawns house and tal to her little sister every day until she tells lavitar and what route to find it on
You can only get bagon in pearl. (and other GBA games) But you can catch lavitar on route 207. If you use the poke rader. They are kind of rare.
Catch a lavitar at island 5 and train it into a pupitar and eventually in the Pokemon league it should evolve into a tyranitar.
trade trade
lucas/dawn little sister at some point will tell you she saw lavitar on news at route 206
you can't