well, you play haromonic chords just like you play regular hamonics...only make a chord shape. you know how to make a regular harmonic right? lightly touch the string? now (what i do) put your fingertips over the frets you want the harmonics, and pluck the strings with your right hand.
if you want a good book, look at
www.deanpeer.com. find his book for sale, and that should help you! here is a link to an example of whats in the book, its got an example of Dm7 and c6/9 chords. give it a look
http://www.deanpeer.com/Book.html
