Allen Carr's EasyWay Seminar
EasyWay Seminars are held with about 25 people, are about 5 hours long, and cost around $425 to attend. The seminar content is based on Allen Carr's EasyWay to Quit Smoking book, which is also reviewed on this site.
If you're thinking you want to try this seminar, I'd definitely recommend taking a look at the book first, to make sure it makes sense to you. My personal impression of the EasyWay Method to Quit Smoking is that it is a little short on actual 'method' in the sense that you never get explicit directions on how to quit. See my comments about the EasyWay Method book for more.