hmm, I'm not so confident in recommending clubs these days as an entry point into activities like climbing and canyoning.
It's true that some clubs are pretty good and have dedicated, experienced and skilled people leading trips - but my experience is that these days that's become the exception rather than the rule. The problem for a newcommer is that they won't have the judgment to be able to decide whether a proposed club trip is likely to be safely run or not. In general (I concede that there are exceptions) club trip leaders don't need (or have) any recognised qualifications. And because many clubs are places with a transitory population (unis etc), leaders change, experience is lost and trips go out led by quite inexperienced people. How is "Joe Nube" going to know this? Consequently there have been a number of fatalities, group evacuations and other accidents on club trips in the Blue Mountains (where I live) in recent years.
Commercial guiding companies - in general (yes, there may be a small number of exceptions) commercial trips are well run and in the main guides are qualified and experienced. And as time goes by this is improving more. Consequently there have been no deaths on commercial canyoning, abseiling or climbing trips in the Blue Mountains. Whereas there's been a number of deaths on organised group or club trips. And there have been many more minor accidents, near misses, overnight strandings and evacuations of non-commercial "organised" groups compared to the adventure companies.
My experience is that a paid guide will also make more of an effort to impart skills and knowledge during a structured instructional course (less so on a paid "jolly" day) although I may be biased because I've worked in the past as a commercial climbing and canyoning guide
My recommendation is to do a canyon leaders course through an adventure company. You'll learn a lot about group management, trip planning, problem avoidance, personal self rescue, group self rescue, emergency procedures, gear etc. It will cost a couple of hundred bucks but this is still a very cheap way to enter a new sport, especially a sport where the consequences of a stuff up might mean dying - we aren't talking golf...