Go through tunback cave, its the cave entrance at sendoff spring, which you get to by going past lake varlor, (dont go in lake varlor) going a little further to the right you should see a path. (spring path)
Absol is the Pokemon before Giratina. Absol's number in the pokedex is 209 and Giratina's number is 210. This is the one in the Pokemon platinum POKEDEX.
Giratina is #487 in the national pokedex, and it is a Ghost-Dragon type Pokemon.
After you defeat the Pokemon League and receive a National Pokedex, you can go to Spring Path and follow it all the way through. Eventually, you will encounter Giratina.
Ive got 260 of the pokedex, and so far it's giratina. It might not be the heaviest but i think it is.
my friend said to use lots of net balls and timer balls which you can get pokenemon leand and you have to have a nation pokedex
You have to get the National Pokedex and then you have to go to the route with the ruin maniac (forgot the route name) and on the right hand side there is a path called Spring path and you follow it to get to Giratina.
No, there is not a Pokedex after the National Pokedex in Pokemon Diamond Version.
Giratina's origin forme is not present in Pokemon Diamond only it's Altered forme. Whilst you can still attach the Griseous Orb to it, it will only boost Giratina's stats ,not change it's form, to do that you need to play Pokemon Platinium.
You can't games you find Giratina in are Pokemon Pearl, Diamond and Platinum if you want to get Giratina badly get Pokemon platinum because in that game he is the main Pokemon!
he should be in turn back cave after you get the natinal pokedex =)
diamond pokedex number 80 is Barboach
Riolu