Andy,
I have done both the Extracta course and Four Prochem courses. The Extracta course was carried out on a Saturday and i travelled from South Wales to attend this one, with hotel accommodation thrown in. I did not have to pay for any of these courses as i had been made redundant in 2002.
The Extracta one could be described as not very good by some people, but my personal opinion was that the guy who did the training for them, Ken of kenclean systems was very knowledgeable and the course was very hands on. He did practicle demonstrations and we could have a go. I think there was only six on this course, so everyone got to have a go. I was so impressed that i eventually spent £5k on equipment and had no problems with it. They might not look like other machines, but they are a means to earn money.
The Prochem courses are also very good, but i get the impression that they are rehearsed over and over again and push their products at every opportunity. Again with Prochem they set a standard in our industry, and i heavily use their chemicals because i know i can trust them. I did have a chemical pack from Extracta, but they are not marked, or they were not at the time, with their ph level, so i was never really sure.
Both courses provide you with lunch. Prochem gives you lunch and a desert and Extracta sends somebody down the chippie.
I would try the Extracta course as it's near you, then go out and clean some carpets. When the money comes in, do the prochem ones or even ncca or the other one. If you can afford it as well, buy the Extracta carpet manual. They are expensive but you will learn from this as you go on.
Hope this helps
Dave