Let's see... You can get a good rod at the house at silence bridge. (In Kanto, below Lavender Town)
Use a fishing rod.
A Fishing Guru in Olivine City has it.
You can get an Abra at the gamecorner in golden rod and evolve it.
surf on water or get a fishing rod
I know that you get the super rod in Route 12.
go in the golden rod under ground tunnel
At the Flower Shop in Golden Rod City.
the house nearest to the pokemon center in olivine city
you get it in a house in olivine city hope this helped you
go to golden rod and look for a tent where a man can change your pokemon's name
There is only old, good, and super rods in Pokemon Heart Gold.
one is in golden rod and i forgot where the other one is