Surfing in Violet City is your best bet, it's also in Ecruteak and routes 22/28/30/31
Move the little circle thing to the very top of the circle and you'll get the PokeFlute station.
Now for a question of my own.
I have two Swamperts in the daycare, yet they will not make any eggs, when i talk to the old man outside he asks me a question with a yes or no answer. No matter which answer I give or how many times I answer, he won't stop asking this question and my Swampert won't produce any eggs.
Anyone know what the hell the guy is on about?