I've got one large bookcase on our first floor, in the den/library. We had it custom-made to match the oak woodwork when we first bought the house eight years ago. This bookcase holds my favorite smaller collections.

The third floor attic area has two larger bookcases, and a bunch of piles of books. I'll add photos of them later.

Here's a picture of the full bookcase. It has seven shelves, with a division down the middle. The lower two shelves are deeper, with a ledge between the fifth and sixth shelf (counting downwards). The bottom three shelves are taller, also.

Left 1st shelf (top): Dan Simmons
Left 2nd shelf: mostly Stephen King
Left 3rd shelf: Stephen King
Left 4th shelf: Joe Hill; Ray Bradbury
Left 5th shelf: Caitlin R. Kiernan; Philip Jose Farmer
Left 6th shelf: Will Eisner
Left 7th shelf: Kitchen Sink Press comic strip books

Right 1st shelf (top): Ray Bradbury signed firsts
Right 2nd shelf: Iain (M) Banks
Right 3rd to 5th shelf: Joe R. Lansdale limiteds and HC firsts
Right 6th shelf: Neil Gaiman
Right 7th shelf: Neil Gaiman; George Herriman Krazy Kat compilations