Both IAM and RoSPA Wiltshire groups offer taster sessions which you can do before you sign up. They are very relaxed, not hard sell at all just to give you an idea of what it's like.
IAM were doing them at the old Little Chef in Chippenham, and RoSPA do them at the Divine Cafe outside Calne. RoSPA call it SkillShare http://www.wiltshireroadar.co.uk/oth...ion/skillshare
They both do them once a month and you can just go along have a chat and go out for a ride with one of the observers (thats what IAM call the instructors) or tutors (RoSPA's name for the instructors).
I think they both start next month but if you give either a call they'll tell you. If not the dates will be on the websites soon I'm sure.