I charge $90/hour for a coaching session, with a reduced rate for group workshops. I prefer individual sessions because of the intensive focus on your work. However, a group session can be effective in certain cases.
As with an hour spent with a massage therapist, an attorney, or any consultant, a single session of an hour or two will offer a lot of value, introducing you to new ideas and new techniques, helping you to rethink your approach to a particular challenge (or several).
Recurring sessions (once a week, once every two weeks, once a month) will allow you the opportunity to build quickly on what you are learning.
I am based in Denver, Colorado, and my clients are primarily local. I am open to book coaching long distance (over the phone, for instance), but it is certainly a different type of communication. I would be open to discussing the logistics and goals for long-distance opportunities on a case-by-case basis.