Shopping zone is wordpress theme that design for Amazon Store. It also look great for your images gallery site. Thumbnail in homepage generated automatically. It get the first image in post and set it as the thumbnail. So, you no need to set any custom field or any settings.
Shopping Zone Demo | Download Shopping Zone WP Theme (35)
This wordpress theme plan to release under Creative Common 3, so you can share, copy and distribute and adapt this wordpress theme for your work.
Good .. nice theme