You get it from a Fishing Guru on Route 12 at the Kanto region.
Chat with our AI personalities
Super rod all over the place until you find a wailmer
Go to the rocky beach area and use the super rod.
yes, in the dragon's den. although, it wont be very strong. your best bet is a super rod
Talk to the fisherman inside a house on Silence Bridge (below Lavender Town). :)
In Pokémon SoulSilver, you can get the Old Rod in Route 32 in Johto, you can get the Good Rod in Olivine City and you can get the Super Rod in Route 12 in Kanto.