In his book, and the DVD of a couple's workshop, Gottman clearly spells out the seven principles, provides exercises, check lists, and so on. He dispels myths, and in a very accessible way, spells out a path to a loving and passionate relationship. His research shows that as long as couples have five positive/productive interactions to counteract one poor interaction, the relationship will last.
The book is available everywhere; the DVD workshop, The Art and Science of Love, is only available at his website: www.gottmaninstitute.org The series is 5 DVDs and a workbook. There are lecture portions for you to watch, and then do the corresponding exercises.
Gottman's work is especially good for couples that fight a lot. For couples that don't fight much, you might feel that you can't relate to the problem-solving principles. However, the first four principles provide a great foundation for your couple, and the last principle focuses on creating shared meaning.
This is definitely worth your reading/watching/working time.