Melvin Helitzer, Comedy Writing Secrets. This book is what convinced me to look into the rhetorical devices in wit. Helitzer discussed number of rhetorical techniques, although he didn't name them. Helitzer also presented a procedure for reforming cliches, inspiring me to look for more procedures for wit. (I'm a software person: I love procedures.)
Ronald Carpenter, Choosing Powerful Words: Eloquence That Works (Part of the Essence of Public Speaking Series) (Essence of Public Speaking Series). This is the other book that convinced me to investigate rhetorical devices and procedures for constructing them. Carpenter teaches public speakers to use powerful language. He presents techniques, rules, hints, exercises, and procedures. If you want to apply rhetorical techniques in public speaking, read this book.
Richard A. Lanham, A Handlist of Rhetorical Terms. Beautifully informative and cross referenced, this contains what you need to know about rhetorical devices. Just don't get overwhelmed by all the Latin and Greek nouns: you don't have to know all of them.
Judy Carter, The Comedy Bible: From Stand-up to Sitcom--The Comedy Writer's Ultimate "How To" Guide. The first section, on stand-up comedy, is excellent. Her approach is almost a formula:
Gene Perret, Comedy Writing Workbook. To learn to be a comedian, get this book and work through the exercises.
Gene Perret, The New Comedy Writing Step by Step. A more casual read than his Workbook, this book discusses some comedy writing techniques. I was particularly taken with his organized listing technique in which you explore a topic by writing lists of people, places, things, events, and cliches associated with the topic in both a positive and a negative way. I was also impressed by discussion and example of "routining," putting jokes together into a routine.
Judy Carter, Stand-Up Comedy: The Book. This is an older book. The view of what elements constitute stand-up comedy is broader, but she has refined her instructional skills since that time.
I haven't gathered this material yet. If you wish to suggest a site, let me know.