you have to go into the big forest and around that area there will be a pikachu.
You can catch Pikachu in Viridian Forest and at the Power Plant.
You can catch it in Viradian Forest at about level 4 or lower.
Elekid is at the Power plant.(where u catch pikachu).
You have to beed pikachu. That is the only way.
What I did was catch a Pikachu in Viridian Forest, then level it up until around 35 and gave it a ThunderStone.
I'm not sure but I think if you catch enough Pikachu you should get 1
Two places to find pikachu are in viridian forest or in the power plant.
step 1 catch pikachu step 2 train him
you catch zapdos... and you can get the TM thunder in there so..... You can also catch: magnemite magneton electabuzz pikachu Voltorb and electrode
Pikachu evolves with a thunder stone.
Catch a pikachu, and you'll have a small change that it is holding one. The best spot to do this is in the power plant.
You catch Pikachu in Veridian Forest