At what age is a dog/puppy too old to start showing? I have read the post about ringcraft classes, but am curious as to whether a puppy has to begin at a very young age in order to 'know the ropes' or whether an older pup would still be able to compete.

There is no clear cut answer. For some it's easier to start earlier, for others better to wait. Really what matters more than anything else is that the dog/puppy is happy and confident in new situations and happy to be handled by complete strangers. It's easier to teach a puppy to stand but not at all impossible to train an adult either.

My old girl who became a Champion was never shown until nearly a year old and I've got a 4 year old here that I fully intend to show at some point but haven't shown yet.

Personally I don't do ringcraft any more as for my breed, it can put them off. For other breeds it's ideal.

I took Fleur to her one and only breed show when she was almost three years old. She walked in as though she had been doing it all her life, stood properly, trotted nicely. It was me who hadn't a clue. Being slightly deaf and unable to hear clearly as it was noisy didn't help. Tayo was almost nine months, had fun trying to lick the judge to death, got best puppy and then tried to hug the group judge. I may take him again in the future. Belgian people seem very friendly and encouraging, more than another breed I tried to show in the past.

Pleny of dogs in my breed have come into showing as adults when their owenrs got curious to fdn out more about the breed and were persuaded to have a go showing.

A pup I sodl purely as a companion was first shown at our club open show at nerly two, was I think 2nd out of two and  third out of three in his classs, and they thought tht was that. 

they then some months later entered an all breeds open show and were Best of Breed from a small entry, then won the Hound Group, and then Reserve Best In show.

Their next show was their first Championship show, people helped them buy a benching chain etc, and they won their class, best Dog the CC and Best of Breed.

He was a bit of a Marmite dog, some judges loved him some did not, he was on the tall side, so he often won or was at the end of the lien, over the next two years they won his second and third CC's to make him a champion.

By this time they had bought him a canine companion who had the same father, and she too did well for them, and became a champion.

He now judges the breed..

Belgian people seem very friendly and encouraging, more than another breed I tried to show in the past.

That's so true. I spent years (decades in fact!) showing two breeds on and off, never really getting into it. Then at my first show with a Belgian was so warmly welcomed that I felt like I had joined a new family, and the rest is history -it's so much a social occasion with this breed.

Wonderful story Brainless!

With the same breed as Brainless we had a dog puppy that we'd bought purely as a pet. We just happened to go to an elkhound walk one Sunday and kept being approached by people asking us if we were going to show him. He had no ringcraft training but was handled by his breeder . He went on to win BPIS at his first show and eventually 4 cc's.
If you've never shown before ringcraft training is as important for the handler as the dog. I enjoy going as much for the social side as the training for my dog .

I hadn't really considered it as I assumed that all show dogs were started at ringcraft really young. My dogs have both enjoyed training classes so they are used to a similar environment. I am now wondering whether I should give it a go for the experience, I think my dogs are gorgeous (naturally) but it would be interesting to find out what others (that know what they're doing) think. The older one is spayed, would that rule her out? I'd only want to do it for fun and I don't want to breed as it scares the bejasus out of me!

The older one is spayed, would that rule her out?

No -although in some breeds it can alter the coat quality. Also you need to officially inform the KC that she has been spayed in order to be allowed to show her. Form here: http://www.thekennelclub.org.uk/forms/neutered-dog/

Thank you to everyone for your responses, it's really made me think. I will look at the showing section of CD and try to visit some smaller shows to see how it's done. Been to Crufts three times, but that feels a bit like sitting your A levels when you haven't learned to read yet!! There is a ringcraft class locally, so I might check that out too. I am a bit of a scaredycat and need to do my research before plunging in, so it's good to know it's not too late. Thanks again, it's appreciated.