Hi Ian,
There is a lot of info here and a lot to go through but as you say just take it one step at a time.
You know your full circumstances so it's easier for you to look through the visa types (or go to an agent) than it is for us to guess. The visa links are at the top of the "Please read...." post.
Things to consider when looking at a visa is where you want to live and whether you are happy coming to Oz without a job (which is what most people do). Where do you want to live? Do you mind living somewhere out of the major cities for a while? Do you want a permanent or temporary visa?
Sponsorship gives you a job but you are tied to living in that area for a specified amount of time, and I think that most of them are temporary (although you can apply for a permanent visa).
Coming through the skilled independent route gives you permanent residency and you get to choose where you want to live but you have to find a job when you get here. We went the skilled independent route - there is a points test in the "please read..." post to see if you have enough points.
We have 2 agents on the forum and I think that Alan Collett has a branch in the UK.
We used an agent in the UK called the
Emigration Group who also have a sister company in NZ. They have a seminar coming up on June 29th in Peterborough, UK - if that's anywhere near you.
Regards,
Karen