Oops, it doesn't look like 'book book day' is a national day..

Other days

buddy

Buddy Day
pumpkin

Pumpkin Day
girl friend

Girl Friend Day
artists

Artists Day
unicorn

Unicorn Day
ruby

Ruby Day
bow tie

Bow Tie Day
cuddle up

Cuddle Up Day
ormille

Ormille Day
comfy

Comfy Day