In Pokémon World Online I have been trying to catch a Pikachu for like 2 hours and I haven't had any luck yet. Is there a fast way to go about it?
I ran around in Viridian forest and got one in half an hour, my friend walked around there for three hours and gave up. It's very random, but there is as far as I know no way to increase your odds of encountering any particular species in the game. Just don't give up, you will find it sometime!
They appear on a higher level at the power plant though, so if you don't want to train a level 3 Pikachu all the way you should definitely catch one at the power plant.