I recommend:
- Kamakura - Stay away from the beach BUT visit the Big Buddha! There are also plenty of Zen Gardens.
- DisneySEA - I know you said no amusement but it's just that amazing.(I've already been twice and will once more).
- Akihabara - Robots, electronics and Sega World.
- Fuji-Q - It has the World Record for steepest drop.
I currently live in the Tokyo area. I usually check this page for ideas:
Visit Japan 2011 (Japan travel UPDATEs) - Wall | Facebook