一冊[issatsu] one copy (e.g. book)
冊子[sasshi] book
冊子[soushi] written work (esp. a bound text, as opposed to a scroll)
冊数[sassuu] number of books
冊立[sakuritsu] imperial investiture

数冊[suusatsu] several volumes (books)
短冊[tanzaku] long, narrow card on which Japanese poems are written (vertically)
分冊[bunsatsu] separate volume
別冊[bessatsu] separate volume

愛書[aisho] great love of books
愛読書[aidokusho] favourite book
悪書[akusho] harmful book
案内書[annaisho] guidebook
移動図書館[idoutoshokan] mobile library

遺言書[yuigonsho] testament
遺書[isho] note left by dead person
医書[isho] medical book
一つ書き[hitotsugaki] an item
一書[issho] one letter