Kris, if you check out the www.alexandertechnique.com link above you can click on "where to find a teacher in the UK." A few of those folks' website list lesson fees at around 30 pounds. Once you tap into the list of teachers in your area, you might find out if they offer introductory workshops. Here in New York, many Alexander teachers offer intro. workshops free so that people can become familiar with AT. Also, group classes can be more economical than private, so you could find out if the teachers in your area run group classes as well. Again, my friend Leland runs group classes in addition to private lessons and his students really get a lot out of them, so a private lesson isn't necessarily the only way to go. (If any NY metropolitan area catters are interested, you should check out www.freeyourneck.com to find out more about his classes--he's a great teacher.)
Margaret