Bible.org
Bible.org: An Introduction to the Book of Nahum
This is an excellent outline of the contents of the Book of the prophet Nahum from the Hebrew Scriptures.
Other
Moeller Haus: Isaiah Commentary
This is a chapter-by-chapter commentary on the Book of the prophet Isaiah from the Hebrew Scriptures.
Other
Hosea: The Prophet and the Prostitute [Pdf]
This is an interesting commentary on the Book of the prophet Hosea from the Hebrew Scriptures.