Remember James your my long lost brother!
Why not look at some job adds to see the skills they require then go away , look at the courses and see which one is a fit. You'll need to gain the relevant knowledge, no one will employ you on the basis of a qualifcation alone. Also you may need to start off below system admin.
One of the problems is not the interview process but the selection process. I have seen some good people fall by the wayside because it is standard company / school / college policy to ask for certain things. Sometimes Certs are a way of getting your foot in the door or simply letting you shine out. If the schools is looking for 6 candidates to take to interview (and they expect 1 or 2 to pull out or not turn up) then how do you shine out from the 40+ applicants they have had?
The thing that always hampers me in these is either the degree thing or not being a qualified teacher. I know that long term I will need a degree to progress down certain lines ... but it is not the be all and end all of things. Other Certs ... I had a chat recently with someone (and now regretting not taking their offer) who asked me about Certs ... I told them that if they wanted me to learn about implementing a specific technology I would do, I would take 3 months to get up to the required standard, during which I would also be asking the advice of others who are doing it already, and learning from experience. My two greatest assets are to be able to learn quickly, and to have a fantastic network of professionals who can give help and advice.
If you can prove you can learn quickly, adapt, plan and communicate then that will do wonders for you ... but you have to learn to shine ... either through Certs or a wonderful CV (or both).