Legend of Zelda: The Wind Waker (Import)

Blue Potions:
Use the grappling hook on the monster plants on the island with the big tree to obtain a venus flytrap item. This item can be traded to the plant shaman inside the big tree's cave.

Gold Potions:
After completing the first cave, capture a fairy in a bottle and go back to the island you started the game on. Find the old woman and use the bottled fairy on her. Speak to her, and you will receive a gold potion. Speaking to the old woman will refill the gold potion if used up.