Planet Minecraft

I need something that will take all of Block X and change it into Block Y. So, for example, turn all dirt blocks into stone. Is there a mod that will allow me to do that?
Thanks in advance!

Equivalent exchange does this to a degree

World edit...

Download Single Player Commands, Once you have the mod installed. Go to your world and Type //wand. Then you should have a wooden ax. Then left click on a block then right click on another block. This makes a invisible box. Then for what your wanting type: //replace dirt stone . Then that should do it. Hoped this helped.

Do you want it as an item or as a block.
Equivalent exchange will change certain blocks to certain blocks (items)
While World Edit will change the selected blocks (e.g.dirt) to (e.g. stone) (Block form)

Do you want it as an item or as a block.
Equivalent exchange will change certain blocks to certain blocks (items)
While World Edit will change the selected blocks (e.g.dirt) to (e.g. stone) (Block form)

The latter, so it sounds like World Edit is what I need! Thanks a lot for the help everyone