They attract rare Pokemon (ex pickachu and the like)...
I'm not sure whether the pokeblock level has any affect... It could, I'm not sure
Green!
When you enter the Safari Building (where you pay the 500 Poke to get in) there should be a machine with 6 different colored dots on it. Go to it and you can customize your Safari Zones
You buy them in the Pokemon markets.
you will find it in the safari zone, in a poke ball.
You can't catch it using Poke Balls, 'cause it is'nt in Pokemon Emerald... But you can trade with other players, of other versions of the game...
Green!
In emerald you get them in the contest hall by making them with berries.
When you enter the Safari Building (where you pay the 500 Poke to get in) there should be a machine with 6 different colored dots on it. Go to it and you can customize your Safari Zones
You cant get poke blocks in Pokemon xd gale of darkness. They are only aquirable in ruby, Sapphire, and emerald.
You buy them in the Pokemon markets.
it is on the ship in the water
you can use it to awaken your pokemon in battle
you have to give it poven or poke-blocks and train it
you will find it in the safari zone, in a poke ball.
Get a link cable and someone else with emerald and go upstairs in the poke center
By going to his backpack and taking a poke ball out of it.
They never want to eat every again. You can only give so many Poke-blocks to them. If they let you give unlimited food to your Pokemon, then you Pokemon would be a master at all types of contest. So if you want that Pokemon to me a Master contest winner, plan what kind of blocks you want to give it.