I want to evolve my slowpoke and seadra but I don't have the kings rock. Where do I get them?
route 13 look here for more details
Firstly Seadra evolves with a Dragon scale not a kings rock. And you can get it on route 13. A man will give you one but its a random chance. He has other items he gives you too. Heres a tip you can save before talking to him and you can reset the game if its not the item you want.