This is a just issued second edition of the classic text by Katz. The text is available from the bookstore as well as online booksellers. Unfortunately, there is not much of a discount/used market for this new edition.
I will also hand out copies of my lecture notes.
Here is a guide to reading the text that shows what we will and will not cover.
There are a gazillion other digital design textbooks out there that you might want to look at. Among the better ones are:
M. Morris Mano, Digital Design, 3rd Edition, Prentice-Hall, 2002.
J. Wakerly, Digital Design Principles and Practices , 3rd Edition, Prentice-Hall, 2000