Blue Power Nut:
To get a Blue Power Nut, you must first catch a Small Fish. Take the Small Fish and throw it in the pond but the Fisherman's Tent. The Water Imp will then give you the Blue Power Nut. It keeps you from getting sick on rainy days. Snowy days are another matter.
Full Moon Berry:
During the Fall, the Flower Shop Calendar will have smiley faces on the 10th, 11th, and 12th. Go to the Restaurant on top of Moon Mountain on these days. Near the Restaurant, there are two trees close to each other. If you press A in between them, you'll receive the Full Moon Berry. It sells for more than the other Mountain items.
The Marble is essemtial to getting a Power Berry. First, you must plant a mixture of Moondrop Flowers and Pink Cat Mint Flowers. There must be a total of 8 three-by-three Flower Beds. If you're doing it right, either the Kissing Couple or the Old Couple will come by to look at them. When they're all fully grown, Stu will come by and ask for a Flower. He doesn't have any money, so he will trade you a Marble for a Flower. Take the Marble, then give it to the Harvest Sprites. Because it is a "shiny, round thing," they will give you a Power Berry if you give them the Marble.
Moon Mountain before Bridge:
You can get on top of Moon Mountain before the Carpenters rebuild the Bridge. Go to the Tree behind the Carpenters' House. Go to the trunk and press A. You will then be able to climb the Tree. You can climb to the top and visit the Moon Mountain Summit. To get off, just go to the edge right next to the Tree and press A. You'll jump off of Moon Mountain.
To get the Music Box, you must first get the Treasure Map. The Treasure Map is found in the Hole in the Tree on your Farm. To get the Music Box, dig with your Hoe about 11 times on the spot where lines from the Dog House and the Tree connect. You then have to be good friends with Rick. Take the Rusty Music Box to Rick and have him fix it. You then give the Music Box to the Girl you're trying to woo. You can keep diigging up the Music Box each time you give it to a Girl. You have to get Rick to fix it each time though.
Old Wine and Reviving Vineyard Tree:
First, you need to become good friends with the Bar Owner by giving him Wild Grapes and Veryberries. Once you're good enough friends with him, he'll give you the Old Wine. You then need to become friends with the Harvest Sprites. Become good enough friends with them, and they'll notice the Old Wine and talk about the Harvest Goddess. Next, you take a something home grown and throw it in the Harvest Goddess's Pond. Ask her to revove the Vineyard Tree. In about two months, Karen will come by and ask you to dance with the Keifu Fairies. This is Karen's Photograph.