I saw this location on a website that lists drum circles all across the country and in other parts of the world. I checked it out last year, but never found any drummers there. I think it would be a great location for a drum circle, but we need to keep in mind that it's private property. The location is in an obscure area of the Stanford Campus. It's not really a garden at all, but more like a small rectangular forested area, bounded on four sides by campus streets. The sculptures, done by artists from New Guinea, are scattered around and are somewhat interesting. Two of the sculptures, made of wood, are hollow and can be used as drums. To use them, some sort of striker or mallet will be needed. There are several benches in the area but I didn't see any restrooms. Bring a chair or something to sit on.
You can see the exact location by looking at the map link above, or you can set your GPS to the intersection of Lomita Drive and Santa Teresa Street on the Stanford Campus. There is plenty of street parking that is unregulated on weekends.