Tottori, head to the ocean.. make a right on the only road that runs along the water. You will come to the little fishing village. There is a board shop in the only strip of stores. Dude's real friendly. Surf's right out front of the shop.
Weekends are packed, especially in the summer. Tons of locals interested to see some Gai-jin, but respect the rules as you would expect them to on your turf.